Application Report
SZZA036C – December 2002 – Revised June 2016

Understanding and InterpretingStandard-Logic Data Sheets
Stephen M.Nolan, Jose M. Soltero, Shreyas Rao
ABSTRACT
Texas Instruments (TI) standard-logic product data sheets include descriptions of functionality andelectrical specifications for the devices. Each specification includes acronyms, numerical limits, and test
conditions that may be foreign to the user. The proper understanding and interpretation of the direct, andsometimes implied, meanings of these specifications are essential to correct product selection andassociated circuit design. This application report explains each data sheet parameter in detail, how it
affects the device, and how it impacts the application. This will enable component and system-design
engineers to derive the maximum benefit from TI logic devices.

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7
8
9

Contents
Application Note Outline .................................................................................................... 2
Introduction ................................................................................................................... 2
Top-Level Look at the TI Logic Data Sheet .............................................................................. 3
3.1
Device Summary .................................................................................................... 4
3.2
Pin Configuration and Functions .................................................................................. 6
3.3
Absolute Maximum Ratings ....................................................................................... 6
3.4
ESD Ratings ......................................................................................................... 7
3.5
Recommended Operating Conditions ............................................................................ 8
3.6
Electrical Characteristics ........................................................................................... 8
3.7
Live-Insertion Specifications ....................................................................................... 9
3.8
Timing Requirements ............................................................................................. 10
3.9
Switching Characteristics......................................................................................... 10
3.10 Noise Characteristics ............................................................................................. 11
3.11 Operating Characteristics ........................................................................................ 11
3.12 Parameter Measurement Information........................................................................... 12
Dissecting the TI Logic Data Sheet ...................................................................................... 14
4.1
Summary Device Description .................................................................................... 14
4.2
Revision History ................................................................................................... 24
4.3
Pin Configuration And Functions ................................................................................ 24
4.4
Absolute Maximum Ratings ...................................................................................... 24
4.5
Recommended Operating Conditions .......................................................................... 27
4.6
Electrical Characteristics ......................................................................................... 35
4.7
Live-Insertion Specifications ..................................................................................... 47
4.8
Timing Requirements ............................................................................................. 47
4.9
Switching Characteristics......................................................................................... 50
4.10 Noise Characteristics ............................................................................................. 54
4.11 Operating Characteristics ........................................................................................ 55
4.12 Parameter Measurement Information........................................................................... 56
Logic Compatibility ......................................................................................................... 56
Detailed Description........................................................................................................ 57
Application and Implementation .......................................................................................... 57
Power Supply Recommendations ........................................................................................ 58
Layout ........................................................................................................................ 58

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1Application Note Outline
10
11
12

1

www.ti.com

Conclusion .................................................................................................................. 58
Acknowledgments .......................................................................................................... 58
References .................................................................................................................. 58

Application Note Outline
This application report is organized into five main sections:
1. Introduction
2. Top-Level Look at the TI Logic Data Sheet. Overall layout and component parts of a data sheet are
explained.
3. Dissecting the TI Logic Data Sheet. JEDEC definition, the TI definition, an explanation, and, where
possible, helpful hints are presented for each specification term commonly found in TI logic data
sheets.
4. Logic Compatibility. Information in TI logic data sheets for determining the interface compatibility
between different logic families is explained.
5. End matter, including the Conclusion, Acknowledgments, and References sections.

2Introduction
This application report is a synopsis of the information available from a typical TI data sheet with the
purpose of assisting component and system-design engineers in selecting Texas Instruments (TI)
standard-logic products. Information includes a brief description of terms, definitions, and testingprocedures currently used for commercial, automotive and military specifications. Symbols, terms, anddefinitions generally are in accordance with those currently agreed upon by the JEDEC Solid State
Technology Association for use in the USA and by the International Electrotechnical Commission (IEC) forinternational use.

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3

Top-Level Look at the TI Logic Data Sheet
The TI logic data sheet presents pertinent technical information for a particular device and is organized forquick access. This application report dissects a typical TI logic data sheet and describes the organizationof all data sheets.
Typically, there are ten sections in TI-logic data sheets:
1. Front Page(a) Features(b) Applications(c) Description(d) Device Information Table(e) Front-Page Graphic(s)2. Table of Contents
3. Revision History
4. Pin Configuration and Functions
5. Specifications(a) Absolute Maximum Ratings(b) ESD Ratings(c) Recommended Operating Conditions(d) Thermal Information(e) Electrical Characteristics(f) Timing Requirements(g) Switching Characteristics(h) Typical Characteristics
6. Parameter Measurement Information
7. Detailed Description(a) Overview(b) Functional Block Diagram(c) Feature Description(d) Device Functional Modes
8. Application and Implementation(a) Application Information(b) Typical Application(c) Design Requirements(d) Detailed Design Procedure(e) Application Curves
9. Power Supply Recommendations
10. Layout(a) Layout Guidelines(b) Layout Example
11. Device and Documentation Support
12. Mechanical, Packaging, and Ordering Information

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Top-Level Look at the TI Logic Data Sheet

3.1

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Device Summary
The first page of a data sheet contains all of the general information about a device (see Figure 1). This
information includes:
1. Title, literature number, and dates of origination and revision, as applicable. Also, the top navigation
contains hyperlinks leading directly to Product Folder, Sample & Buy, Technical Documents (related tothe device), Tools & Software, and Support & Community.

Figure 1. Example of Device Summary
2. The Features section identifies the main features and benefits of the device. This section includes
features in a bulleted form. Figure 2 shows an example of the bulleted features.

Figure 2. Feature Bullets
3. The Applications section for the device identifies the application scenarios for the device. Figure 3
shows an example of typical applications.

Figure 3. Typical Applications

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4. The Description section provides a brief description of the device and its functionality

Figure 4. Brief Description of Device
5. Figure 5 shows a logic diagram. The device information defines the nominal size of the device in eachof the available packages.
Device Information(1)DEVICE NAMEPACKAGE
SOT-23 (5)SN74LVC1G08

BODY SIZE
2.9mm × 1.6mm

SC70 (5)2.0mm × 1.25mm

X2SON (4)0.8mm × 0.8mm

SON (6)1.45mm × 1.0mm

SON (6)1.0mm × 1.0mm(1) For all available packages, see the orderable addendum atthe end of the datasheet.

Figure 5. Device Information
6. Product-development stage note at the bottom of the data sheet
7. Table of contents to list the contents and the link to the page numbers alongside it.
8. Revision history for the device mentioning the changes to the data sheet with the dates.

4 Revision History
Changes from Revision X (March 2014 to Revision Y
Figure 6. Revision History

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Pin Configuration and Functions
Figure 7 shows all the package options for the device. Figure 8 shows the functions of each pin sorted by
the package list and their corresponding pin locations.

Figure 7. Pin Configuration and Functions

Figure 8. Pin Functions Table

3.3

Absolute Maximum Ratings
The Absolute Maximum Ratings section (Figure 9) specifies the stress levels that, if exceeded, may cause
permanent damage to the device. However, these are stress ratings only, and functional operation of thedevice at these or any other conditions beyond those indicated under Recommended Operating
Conditions is not implied. Also, exposure to absolute-maximum-rated conditions for extended periods may
affect device reliability.

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As Figure 9 indicates, there are two absolute maximums that may be exceeded under certain conditions.
The input and output voltage ratings, VI and VO, may be exceeded if the input and output maximum clampcurrent ratings, IIK and IOK, are observed.

7 Specifications
7.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1)
MIN

MAX

UNIT

VCC

Supply voltage range

–0.5

6.5

V

VI

Input voltage range (2)

–0.5

6.5

V

VO

Voltage range applied to any output in the high-impedance or power-off state (2)

–0.5

6.5

V

VO

Voltage range applied to any output in the high or low state (2) (3)–0.5

V CC + 0.5

VIIK

Input clamp current

VI < 0

–50

mA

IOK

Output clamp current

VO < 0

–50

mA

IO

Continuous output current

±50

mA

Continuous current through VCC or GND

±100

mA

150

°C

Tstg
(1)
(2)
(3)

Storage temperature range–65

Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating
Conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
The input negative-voltage and output voltage ratings may be exceeded if the input and output clamp-current ratings are observed.
The value of VCC is provided in the Recommended Operating Conditions table.

Figure 9. Example of Absolute Maximum Ratings Section
Helpful Hint:
All currents are defined with respect to conventional current flow into the respective terminal of theintegrated circuit. This means that any current that flows out of the respective terminal is considered to bea negative quantity.
All limits are given according to the absolute-magnitude convention, with a few exceptions. In thisconvention, maximum refers to the greater magnitude limit of a range of like-signed values; if the range
includes both positive and negative values, both limit values are maximums. Minimum refers to the smaller
magnitude limit of a range of like-signed values; if the range includes both positive and negative values,
then the minimum is implicitly zero. The most common exceptions to the absolute magnitude convention
are temperature and logic levels. In these levels, zero does not represent the least-possible quantity, so
the algebraic convention is commonly accepted. In this case, maximum refers to the most-positive value.

3.4

ESD Ratings
The ESD Ratings section of the data sheet specifies the Electrostatic Discharge ratings for the device
tested as per JEDEC (Joint Electron Device Engineering Council) standards.
Usually, HBM (Human Body Model) and CDM (Charged Device Model) spec is tabulated as per thequalification process. Machine Model (MM) is discontinued.
ESD Ratings
VALUE

V(ESD)

Electrostatic
discharge

Human body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1)2000

Charged device model (CDM), per JEDEC specification JESD22-C101 (2)

1000

(1)

JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD
control process.

(2)

JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD
control process.

UNIT
V

Figure 10. Example of ESD Ratings Section

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3.5

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Recommended Operating Conditions
The Recommended Operating Conditions section of the data sheet sets the conditions for which Texas
Instruments specifies device operation (see Figure 11). These are the conditions that the application
circuit should provide to the device in order for it to function as intended. The limits for items that appear inthis section are used as test conditions for the limits that appear in the Electrical Characteristics, Timing
Requirements, Switching Characteristics, and Operating Conditions sections.
Recommended Operating Conditions (see Note 4)
SN54LVTH16646 SN74LVTH16646
MIN

MAX

MIN

MAX

2.7

3.6

2.7

3.6

UNIT

VCC

Supply voltage

VIH

High-level input voltage

VIL

Low-level input voltage

0.8

0.8

VI

Input voltage

5.5

5.5

V

IOH

High-level output current

-24

-32

mA

IOL

Low-level output current

48

64

mA

Δt/Δv

Input transition rise or fall rate

Δt/ΔVCCPower-up ramp rate

200

TA

Operating free-air temperature-552

Outputs enabled

2

10

V

10
200

125

-40

V
V

ns/V
µs/V

85

°C

NOTE: All unused control inputs of the device must be held at VCC or GND to ensure proper device
operation. Refer to the TI application report, Implications of Slow or Floating CMOS Inputs, literature
number SCBA004.

Figure 11. Example Recommended Operating Conditions Section

3.6

Electrical Characteristics
The Electrical Characteristics (over recommended free-air temperature range) table, also known in theindustry as the DC table, provides the specified electrical characteristic limits of the device when tested
under the conditions in the Recommended Operating Conditions table, as given specifically for eachparameter (see Figure 12).
Helpful Hint:
Although some parameters, such as Ci and Cio, can be tested with an ac signal, sometimes the electricalcharacteristics table is called the DC section.

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Electrical Characteristics (Over Recommended Operating Free-air Temperature Range (unless otherwise noted))
SN54LVTH16646
SN74LVTH16646
PARAMETERTEST CONDITIONSMIN TYP (4) MAX MIN TYP (4) MAX
VIK

VOH

VCC = 2.7 V,

II = -18 mA

VCC = 2.7 V to 3.6 V,

IOH = -100 µA

VCC-0.2

VCC-0.2

VCC = 2.7 V,

IOH = -8 mA

2.4

2.4

IOH = -24 mA

2

VCC = 3 V

–1.2

–1.2

IOH = -32 mA

VCC = 2.7 V
VOL
VCC = 3 V

2

IOL = 100 µA

0.2

0.2

IOL = 24 mA

0.5

0.5

IOL = 16 mA

0.4

0.4

IOL = 32 mA

0.5

0.5

IOL = 48 mA

0.55

A or B ports(5)

VI = VCC or GND±1±1

VCC = 0 or 3.6 V,

VI = 5.5 V

1010

VI = 5.5 V

2020

VI = VCC

1

1

VI = 0–5

VCC = 3.6 V

Ioff
II(hold)

VCC = 0 V,

VCC = 3.6 V (6),µA

–5VI or VO = 0 to 4.5 V

VCC = 3 V

A or B ports

V

0.55

VCC = 3.6 V,

II

V

V

IOL = 64 mA
Control inputs

UNIT

±100

VI = 0.8 V

7575

VI = 2 V

–75

–75

µA
µA

VI = 0 to 3.6 V

±500

IOZPU

VCC = 0 to 1.5 V, VO = 0.5 V to 3 V,
OE = don't care

±100
*

±100

µA

IOZPD

VCC = 1.5 V to 0, VO = 0.5 V to 3 V,
OE = don't care

±100
*

±100

µA

Outputs high

0.19

0.19

ICC

VCC = 3.6 V, IO = 0,
VI = VCC or GND

Outputs low

55

Outputs disabled

0.19

0.19

ΔICC (7)VCC = 3 V to 3.6 V, One input at VCC - 0.6 V,
Other inputs at VCC or GND

0.2

0.2

Ci

VI = 3 V or 0

4

4

pF

Cio

VO = 3 V or 0

10

10

pF

(3)

On products compliant to MIL-PRF-38535, this parameter is not production tested.

(4)

All typical values are at VCC = 3.3 V, TA = 25°C.

(5)Unused pins at VCC or GND(6)This is the bus-hold maximum dynamic current. It is the minimum overdrive current required to switch
the input from one state to another.

(7)

This is the increase in supply current for each input that is at the specified TTL voltage level, rather
than VCC or GND.

mA

mA

Figure 12. Example Electrical-Characteristics Section

3.7

Live-Insertion Specifications
The Live-Insertion section of the data sheet provides information about the parameters needed for true
live insertion. These parameters include Ioff, IOZPU, IOZPD, and BIAS VCC for precharging purposes. An
example of a typical live-insertion section is shown in Figure 13.

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Live-insertion Specifications for B port Over Recommended Operating Free-air Temperature Range
PARAMETERTEST CONDITIONS

MAX

UNIT

Ioff

VCC = 0,BIAS VCC = 0,

VI or VO = 0 to 1.5 V

10

µA

IOZPU

VCC = 0 to 1.5 V,

BIAS VCC = 0,

VO = 0.5 V to 1.5 V, OE = 0

±30

µA

IOZPD

VCC = 1.5 V to 0,

BIAS VCC = 0,

VO = 0.5 V to 1.5 V, OE = 0

±30

µA

5

mA

10

µA

ICC (BIAS VCC)

VCC = 0 to 3.15 V
VCC = 3.15 V to 3.45 V

BIAS VCC = 3.15 V to 3.45 V,

VO (B port) = 0 to 1.5 V

VO

VCC = 0,BIAS VCC = 3.3 V,

IO = 0IO

VCC = 0,BIAS VCC = 3.15 V to 3.45 V,

VO (B port) = 0.6 V

MIN

0.95

1.05

V

-1

µA

Figure 13. Example Live-Insertion Section

3.8

Timing Requirements
TheTiming Requirements section of the data sheet is similar to the Recommended Operating Conditions
section (see Figure 14). These are timings that the application circuit should provide to the device for it tofunction as intended. This section addresses the timing relationships between transitions of one or more
input signals that are necessary to ensure device functionality and applies only to sequential-logic devices(for example, flip-flops, latches, and registers).
Timing Requirements (Over Recommended Operating Free-air Temperature Range (unless otherwise noted)) (see Figure 2)
SN54LVTH16646
SN74LVTH16646

fclockClock frequency

tw

Pulse duration, CLK high or low

VCC = 3.3 V± 0.3 V

VCC = 2.7 V

VCC = 3.3 V± 0.3 V

VCC = 2.7 V

MIN

MIN

MIN

MIN

MAX
150

MAX
150

MAX
150

MAX
150

3.3

3.3

3.3

3.3

1.2

1.5

1.2

1.5

2.8

2

2.8

tsu

Setup time,
A or B before CLKAB↑ or CLKBA↑

Data highData low2thHold time,
A or B after CLKAB↑ or CLKBA↑

Data high

0.5

0

0.5

0

Data low

0.5

0.5

0.5

0.5

UNIT

MHz
ns
ns
ns

Figure 14. Example Timing-Requirements Section

3.9

Switching Characteristics
The Switching Characteristics section of the data sheet, also known in the industry as the AC table,
includes the parameters that specify how fast the outputs will respond to signal changes at the inputs
under specified conditions of supply voltage, temperature, and load (see Figure 15).
Helpful Hint:
The Switching Characteristics table is sometimes called the AC section, and should not be confused with
the AC small-signal performance because switching characteristics describe the large-signal transient
response of the circuit.

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Switching Characteristics (Over recommended Operating Free-air Temperature Range, CL = 50 pF (unless otherwise noted)) (seeFigure 2)
SN54LVTH16646
SN74LVTH16646
PARAMETERFROM(INPUT)TO(OUTPUT)VCC = 3.3 V± 0.3 VMIN

VCC = 3.3 V± 0.3 V

VCC = 2.7 V

MAX

MIN

MAX

TYP
(8)

MAX

150
1.3

4.5

5

1.3

2.8

4.2

4.7

1.3

4.5

5

1.3

2.8

4.2

4.7

1

3.6

4.1

1

2.4

3.4

3.9

1

3.6

4.1

1

2.1

3.4

3.9

1

4.7

5.6

1

2.8

4.5

5.4

1

4.7

5.6

1

3

4.5

5.4

1

4.5

5.4

1

2.5

4.3

5.2

1

4.5

5.4

1

2.6

4.3

5.2

2

5.8

6.3

2

4

5.6

6.1

2

5.6

6.3

2

3.6

5.4

6.1

1

4.6

5.5

1

3

4.4

5.3

1

4.6

5.5

1

3

4.4

5.3

1.5

6

7.1

1.5

3.9

5.7

6.8

1.5

5.5

6

1.5

3.6

5.2

5.7

tPLH
tPHL
tPLH
tPHL
tPZH
tPZL
tPHZ
tPLZ
tPZH
tPZL
tPHZ
tPLZ

A or B

A or B

B or A

SBA or SAB (9)A or BOE

A or BOE

A or BDIR

A or BDIR

A or B

UNIT

MAX

tPLH

CLKBA or
CLKAB

150

MIN

fmax
tPHL

150

MIN

VCC = 2.7 V

150

MHz

(8)

All typical values are at VCC = 3.3 V, TA = 25°C.

(9)These parameters are measured with the internal output state of the storage register opposite that of
the bus input.

ns
ns
ns
ns
ns
ns
ns

Figure 15. Example of Switching Characteristics Section

3.10 Noise Characteristics
This section indicates a device's noise performance due to power-rail and ground-rail bounce associatedwith the high peak currents during dynamic switching (see Figure 16).
Noise Characteristics, VCC = 5 V, CL = 50 pF, TA = 25°C (see Note 4)
SN74AHCT16541

PARAMETER

MIN

TYP

MAX

UNIT

VOL(P)

Quiet output, maximum dynamic VOL

0.6

V

VOL(V)

Quiet output, minimum dynamic VOL

-0.3

V

VOH(V)

Quiet output, minimum dynamic VOH

4.6

V

VIH(D)

High-level dynamic input voltage

VIL(D)

Low-level dynamic input voltage

2

V
0.8

V

(10) Characteristics are for surface-mount packages only.

Figure 16. Example Noise-Characteristics Section

3.11 Operating Characteristics
The Operating Characteristics section of the data sheet includes the parameter that specifies the powerdissipation capacitance (Cpd) in a CMOS device (see Figure 17). For additional information on how Cpd ismeasured and used to calculate total CMOS-device power consumption in the application, refer to the TI
application report, CMOS Power Consumption and Cpd Calculation, literature number SCAA035.

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Operating Characteristics, TA = 25°C
PARAMETER
Cpd

TEST CONDITIONSPower dissipation capacitance per gate

CL = 0,VCC = 1.8 V

VCC = 2.5 V

VCC = 3.3 V

TYP

TYP

TYP

20

21

23

f = 10 MHz

UNIT
pF

Figure 17. Example of Operating-Characteristics Section

3.12 Parameter Measurement Information
The Parameter Measurement Information section of the data sheet illustrates the test loads andwaveforms that are used when testing the device (see Figure 18).

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8 Parameter Measurement Information
VLOAD
RL

From Output
Under Test

S1

Open

TEST

GND

CL
(see Note A)

S1
Open
VLOAD

tpd
tPLZ/tPZL
tPHZ/tPZH

RL

GND

LOAD CIRCUITINPUTS
VCC
1.8 V ± 0.15 V
2.5 V ± 0.2 V
2.7 V
3.3 V ± 0.3 V

VI

tr/ tf

VCC
VCC
2.7 V
2.7 V

<2 ns
<2 ns
<2.5 ns<2.5 ns

VM

VLOAD

CL

RL

VD

VCC/2
VCC/2
1.5 V
1.5 V

2 × VCC
2 × VCC
6V
6V

30 pF
30 pF
50 pF
50 pF

1 kW
500W
500W
500W

0.15 V
0.15 V
0.3 V
0.3 V
VI

Timing Input

VM
0V

tW
tsu

VI
Input

VM

VM

th
VI

Data Input

VM

VM

0V

0V

VOLTAGE WAVEFORMSPULSE DURATIONVOLTAGE WAVEFORMS
SETUP AND HOLD TIMES

OutputControl(low-level
enabling)

Output

VM
VOL

tPHL

tPLH
VM

VM
VOL

VOLTAGE WAVEFORMS
PROPAGATION DELAY TIMES

0V
tPLZ
VLOAD/2
VM
tPZH

VOH
OutputVM

tPZL

OutputWaveform 1
S1 at VLOAD(see Note B)

VOH
VM

VI
VM

OutputWaveform 2
S1 at GND
(see Note B)

VOL + VD

VOL

tPHZ
VM

VOH – VD

VOH
0V

VOLTAGE WAVEFORMSENABLE AND DISABLE TIMESNOTES: A. CL includes probe and jig capacitance.
B. Waveform 1 is for an output with internal conditions such that the output is low, except when disabled by the output control.
Waveform 2 is for an output with internal conditions such that the output is high, except when disabled by the output control.
C. All input pulses are supplied by generators having the following characteristics: PRR < 10 MHz, ZO = 50 W .
D. The outputs are measured one at a time, with one transition per measurement.
E. tPLZ and tPHZ are the same as tdis.
F. tPZL and tPZH are the same as ten.
G. tPLH and tPHL are the same as tpd.
H. All parameters and waveforms are not applicable to all devices.

Figure 18. Example Parameter Measurement Information Section

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4

www.ti.com

Dissecting the TI Logic Data Sheet
In the following paragraphs, the TI logic data sheet is dissected, and every section and specification is
explained in detail.

4.1
4.1.1

Summary Device Description
Title, Literature Number, and Dates of Origination and Revision
The device number and title appear at the top of every page. The device number is the number of theparent device. The fully qualified part number for a specific device can be found in the Orderable Part
Number table. Figure 19 is a chart to help decode information in the TI logic-device part number.
The literature number is a unique identifier used by TI to identify, store and retrieve a data sheet in internal
files.
The month and year of origination is the first date of publication of the data sheet. If a data sheet ismodified, the revision date (month and year) is added. If there are multiple revisions, only the latest
revision date appears.

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Example:

SN

74

LVC

1
1 Standard Prefix

2

3

Examples:

66

1G
4

SN – Standard Prefix
SNJ – Conforms to MIL-PRF-38535 (QML)

5
6

6
Options

Examples:2 Temperature Range
Examples:54–
Military
74 – Commercial

7

3 Family
Examples:4 Special Features
Examples:Blank = No Special Features
C – Configurable VCC (LVCC)
D – Level-Shifting Diode (CBTD)
H – Bus Hold (ALVCH)
K – Undershoot-Protection Circuitry (CBTK)R – Damping Resistor on Inputs/Outputs (LVCR)
S – Schottky Clamping Diode (CBTS)
Z – Power-Up 3-State (LVCZ)

5 Bit Width
Examples:Blank = Gates, MSI, and Octals
1G – Single Gate
2G – Dual Gate
3G – Triple Gate
8 – Octal IEEE 1149.1 (JTAG)
16 – Widebus (16, 18, and 20 bit)
18 – Widebus IEEE 1149.1 (JTAG)
32 – Widebus+ (32 and 36 bit)

8

9

10

Blank = No Options
2 – Series Damping Resistor on Outputs
4 – Level Shifter
25 – 25-Ω Line Driver

244–
Noninverting Buffer/Driver
374 – D-Type Flip-Flop573 – D-Type Transparent Latch
640 – Inverting Transceiver

Device Revision

Examples:

9

8RFunction

Examples:Blank = Transistor-Transistor Logic (TTL)ABT – Advanced BiCMOS Technology
ABTE/ETL – Advanced BiCMOS Technology/
Enhanced Transceiver Logic
AC/ACT – Advanced CMOS Logic
AHC/AHCT – Advanced High-Speed CMOS Logic
ALB – Advanced Low-Voltage BiCMOS
ALS – Advanced Low-Power Schottky Logic
ALVC – Advanced Low-Voltage CMOS Technology
ALVT – Advanced Low-Voltage BiCMOS Technology
AS – Advanced Schottky Logic
AUC – Advanced Ultra Low-Voltage CMOS Logic
AVC – Advanced Very Low-Voltage CMOS Logic
BCT – BiCMOS Bus-Interface Technology
CBT – Crossbar Technology
CBTLV – Low-Voltage Crossbar Technology
CD4000 – CMOS B-Series Integrated Circuits
F – F Logic
FB – Backplane Transceiver Logic/Futurebus+
FCT – Fast CMOS TTL Logic
GTL – Gunning Transceiver Logic
GTLP – Gunning Transceiver Logic Plus
HC/HCT – High-Speed CMOS Logic
HSTL – High-Speed Transceiver Logic
LS – Low-Power Schottky Logic
LV – Low-Voltage CMOS Technology
LVC – Low-Voltage CMOS Technology
LVT – Low-Voltage BiCMOS Technology
PCA/PCF – I2C Inter-Integrated Circuit Applications
S – Schottky Logic
SSTL/SSTV – Stub Series-Terminated Logic
TVC – Translation Voltage Clamp Logic
VME – VERSAmodule Eurocard Bus Technology

7

DBV

Blank = No Revision
Letter Designator A–Z

Packages

Commercial: D, DW – Small-Outline Integrated Circuit (SOIC)
DB, DBQ, DCT, DL – Shrink Small-Outline Package(SSOP)
DBB, DGV – Thin Very Small-Outline Package (TVSOP)
DBQ – Quarter-Size Small-Outline Package (QSOP)DBV, DCK, DCY, PK – Small-Outline Transistor (SOT)DCU – Very Thin Shrink Small-Outline Package (VSSOP)
DGG, PW – Thin Shrink Small-Outline Package (TSSOP)
FN – Plastic Leaded Chip Carrier (PLCC)
GGM, GKE, GKF, ZKE, ZKF – MicroStar BGA
Low-Profile Fine-Pitch Ball Grid Array (LFBGA)GQL, GQN, ZQL, ZQN – MicroStar Jr.
Very-Thin-Profile Fine-Pitch Ball Grid Array (VFBGA)N, NT, P – Plastic Dual-In-Line Package (PDIP)
NS, PS – Small-Outline Package (SOP)
PAG, PAH, PCA, PCB, PM, PN, PZ – Thin Quad
Flatpack (TQFP)
PH, PQ, RC – Quad Flatpack (QFP)
PZA – Low-Profile Quad Flatpack (LQFP)
RGY – Quad Flatpack No Lead (QFN)
YEA, YZA – NanoStar and NanoFree
Die-Size Ball Grid Array (DSBGA †)Military:– FK Leadless Ceramic Chip Carrier (LCCC)
GB – Ceramic Pin Grid Array (CPGA)
HFP, HS, HT, HV – Ceramic Quad Flatpack (CQFP)J, JT – Ceramic Dual-In-Line Package (CDIP)
W, WA, WD – Ceramic Flatpack (CFP)

10 Tape and Reel
Devices in the DB and PW package types include the R designation
for reeled product. Existing product inventory designated LE may
remain, but all products are being converted to the R designation.
Examples:Old Nomenclature – SN74LVTxxxDBLE
New Nomenclature – SN74LVTxxxADBR
LE – Left Embossed (valid for DB and PW packages only)
R – Standard (valid for all surface-mount packages)

There is no functional difference between LE and R designatedproducts, with respect to the carrier tape, cover tape, or reels used.

† DSBGA is the JEDEC reference for wafer chip scale package (WCSP).

Figure 19. Device Number and Package Designators for TI Devices

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Special features of TI standard logic devices are designated in the device number by abbreviations, as
shown in the following list and defined in the following paragraphs.
• Blank - No special features• C - Configurable VCC• D - Level-shifting diode• H - Bus hold
• K - Undershoot-protection circuitry• R - Damping resistor on inputs/outputs• S - Schottky clamping diode• Z - Power-up 3-state
4.1.1.1

Configurable VCC (C)Configurable VCC is a feature of devices that are designed as dual-supply level shifters, for example,
SN74LVCC3245A and SN74LVCC4245A. Using these devices allows selection of the voltage to be
applied to VCC on the B-port side (VCCB) or A-port side (VCCA) (see Figure 20).
’4245 Pinning’245 Pinning

VCCB
VCCB
OE

VCCA
DIR
A1
•

B1

•

•

•

’424

•

•

•

•

•

•

•

•

•

GND

’LVCC3245’LVCC4245
No Internal Connection

•

GND

GND
Copyright © 2016, Texas Instruments Incorporated

VCCA
A PortVCCB
B PORT

TRANSLATION(BIDIRECTIONAL FLOW)

SN74LVCC3245A

2.3 V-3.6 V

3 V-5.5 V

2.5 V to 3.3 V or 3.3 V to 5 V

SN74LVCC4245A

5V

3 V-5 V

5 V to 3.3 V

Figure 20. Example of Configurable VCC Devices
Designers can use these devices in existing single-voltage systems. When systems become mixedvoltage systems, these devices do not need to be replaced, allowing for quicker time to market.
4.1.1.2

Level-Shifting Diode (D)Devices with D as part of the device number have an integrated diode in the VCC line. Examples arecrossbar switches SN74CBTD3306 (with the integrated diode) and SN74CBT3306 (without the integrated
diode). These devices allow 5-V to 3.3-V translation if no drive is required. Bidirectional data transmissionis allowed between 5-V TTL and 3.3-V LVTTL, whereas only unidirectional level translation is allowed from
5-V CMOS to 3.3-V LVTTL (see Figure 21). The integrated diode saves designers both board space andcomponent cost.

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V CC = 5 V

CBTD
CBT
OE

3.3-V

5-V

SystemSystem± µP± ASIC

± µC

± RAM

± DSP

Copyright © 2016, Texas Instruments Incorporated
5-V to 3-V Translation
5
SN74CBT4VO ± V

SN74CBTD
3

2
1

0

1

2

3

4

5

VI ± V

Figure 21. CBT vs CBTD With Internal Diode4.1.1.3

Bus-Hold (H)A bus-hold circuit is implemented in selected logic families to help solve the floating-input problem
inherent in all CMOS inputs (refer to the application report, Implications of Slow or Floating CMOS Inputs,
literature number SCBA004). The bus-hold circuit maintains the last known input state into the device and,as an additional benefit, pullup or pulldown resistors no longer are needed (see Figure 22). The
advantages of devices with this circuit are board-space savings and reduced component costs.
V CC

DeviceBus-Hold Circuit

Input
Bus

OutputBus

Copyright © 2016, Texas Instruments Incorporated

Figure 22. Benefit of Using Bus-Hold Devices

4.1.1.4

Damping Resistor on Inputs/Outputs (R)Series damping resistors (SDR), denoted by R in the device number, are included at all input/output andoutput ports of designated devices (see Figure 23). The SDRs limit the current, thereby reducing signal
undershoot and overshoot noise. Additionally, SDRs make line termination easier, which improves signal
quality by reducing ringing and line reflections.

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V CC

From Internal
Logic Circuitry

SDR
OutputCopyright © 2016, Texas Instruments Incorporated

Figure 23. Series-Damping-Resistor Option

4.1.1.5

Schottky Clamping Diode (S)Schottky diodes are incorporated in inputs and outputs to clamp undershoot (see Figure 24). The Schottky
diodes prevent undershoot signals from dropping below a specified level, reducing the possibility ofdamage to connected devices by large undershoots that can occur without the Schottky diodes.
1A

1B

1OE
Copyright © 2016, Texas Instruments Incorporated

Figure 24. Schottky Clamping-Diode Device Schematic

4.1.1.6

Undershoot-Protection Circuitry (K)TI undershoot-protection circuitry (UPC) functions similarly to Schottky clamping diodes, with one majordifference. UPC is an active clamping structure. UPC can greatly reduce undershoot voltage, increasingprotection from corrupted data (see Figure 25).

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V CC

V CC

UC †

UC †

V CC

V CC

UC †

UC †

1A1

1B1

1B8

1A8

1OE

Undershoot Clamping
6.3
CBTK vs CBTS Undershoot Protection
5.4
CBTK Output

4.5

VI – V

3.6
2.7
1.8

CBTS Output

0.9
0.0
–0.9
–1.8

6

9

12

15

18

21

24

27

30

Time – ns

Figure 25. Undershoot-Proctection Circuity in K-Option Devices

4.1.1.7

Power-Up 3-State (Z)The power-up 3-state (PU3S) feature ensures valid output levels during power up and ensures the valid
high-impedance state during power down. The output enable pin (OE) must be tied high (to VCC) throughan external pullup resistor (see Figure 26). For more information, see IOZPD and IOZPU specifications in theElectrical Characteristics section.

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V CC

OE

PU3S

OE
Control

OutputCopyright © 2016, Texas Instruments Incorporated

Figure 26. PU3S Circuit Implementation

4.1.2

Features Bullets
The Features section highlights information about the salient functions, features, and benefits of thedevice. Some features bullets provide an indication of functionality and application of the device, such as"Eight D-type Flip-Flops in a Single Package", "3-State Outputs", "Carry Output for N-bit Cascading" (for abinary counter), "Performs Parallel-to-Serial Conversion", or "Bidirectional Interface Between GTLP Signal
Levels and LVTTL Logic Levels". Some data sheets contain electrostatic discharge (ESD) or latch-up test
results and the associated JEDEC test conditions. The following are explanations of some common
features bullets.
• Flow-Through Architecture Optimizes PCB Layout• The data inputs and corresponding outputs are on opposite sides of the package. This feature makes
printed circuit board trace routing easier.
• Bus-Hold on Data Inputs Eliminates the Need for External Pullup/Pulldown Resistors• Active bus-hold circuitry holds unused or non-driven inputs at a valid logic state. Use of pullup or
pulldown resistors with the bus-hold circuitry is not recommended. For more information on bus holdrefer to the TI application report, Bus-Hold Circuit, literature number SCLA015.
• Ioff Supports Partial-Power-Down Mode Operation• This device is fully specified for partial-power-down applications using Ioff. The Ioff circuitry disables theoutputs, preventing damaging current backflow through the device when it is powered down.
• Ioff and Power-Up 3-State Support Hot Insertion• This device is fully specified for hot-insertion applications using Ioff and power-up 3-state. The Ioff
circuitry disables the outputs, preventing damaging current backflow through the device when it ispowered down. The power-up 3-state circuitry places the outputs in the high-impedance state during
power up and power down, which prevents driver conflict.
• Ioff, Power-up 3-State, and BIAS VCC Support Live Insertion• This device is fully specified for live-insertion applications using Ioff, power-up 3-state, and BIAS VCC.
The Ioff circuitry disables the outputs, preventing damaging current backflow through the device when it
is powered down. The power-up 3-state circuitry places the outputs in the high-impedance state during
power up and power down, which prevents driver conflict. The BIAS VCC circuitry precharges andpreconditions the input/output connections on a device port, preventing disturbance of active data on
the bus during card insertion or removal and permits true live-insertion capability.

4.1.3

Package Options and Pinouts
This section contains a top-view illustration of the leaded-package pinout(s) and a bottom view of certain
nonleaded packages. Package dimensions and other package information is available in the Mechanical
Data section of the Semiconductor Group Packaging Outlines Reference Guide, or Analog and Logic
packaging literature number SSZB138A.

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4.1.4

Applications
The Applications section contains a list of the typical system applications the device can used in.

4.1.5

Description
The Description section contains a written detailed explanation of the functionality and features of thedevice.

4.1.6

BGA Packaging Top-View Illustrations and Pin-Assignments Table
This section contains the top-view illustrations and pin assignments for applicable BGA package types.

4.1.7

Device Information
A table is provided that gives the fully qualified orderable part number and topside symbolization for every
package option of the device.
TI has converted to an advanced order-entry system that provides significant improvements to all facets of
TI business, from production, to order entry, to logistics. One requirement is a limitation of TI part numbers
to no more than 18 characters. Based on customer inputs, TI determined that the least-disruptive
implementations would be as outlined below:
1. Package alias
TI uses an alias to denote specific packages for device numbers that exceed 18 characters. Table 1
shows a mapping of package codes to an alias representation.
Table 1. Package Alias
Current
Package Code

Alias

DL

L

DGG/DBBG

DGV

V

GKE/GKF/GQLK

DLRLR - tape/reel packing

DGGR/DBBR

GR - tape/reel packing

DGVR

VR - tape/reel packing

GKER/GKFR/GQLR

KR - tape/reel packing

2. Resistor-option nomenclature
For device numbers of more than 18 characters and with input and output resistors, TI has adopted asimplified nomenclature to designate the resistor option. This eliminates the redundant "2" (designating
output resistors) when the part number also contains an "R" (designating input/output resistors).
Input/Output Resistor
Output Resistor
Current: SN74 ALVCH R 16 2 245 A
New:
SN74 ALVCH R 16 245 A

There is no change to the device or data sheet electrical parameters. The packages involved and thechanges in nomenclature are given in Table 1.
The approximate body size in millimeters are given for each of the package .
4.1.8

Function Table
The function table illustrates the expected logic values on the outputs, when the inputs have the given
stimuli applied.
The following symbols are used in function tables in TI data sheets:

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H
L
↑
↓

=
=
=
=
=
=
=
=
=
=
=

X
Z
a...h
Q0
Q0
Qn

=
=
=

Toggle=www.ti.com

high level (steady state)
low level (steady state)transition from low to high leveltransition from high to low levelvalue/level or resulting value/level is routed to indicated destination
value/level is re-enteredirrelevant (any input, including transitions)off (high-impedance) state of a 3-state output
the level of steady-state inputs A through H, respectively
level of Q before the indicated steady-state input conditions were establishedcomplement of Q0 or level of Q before the indicated steady-state input
conditions were establishedlevel of Q before the most-recent active transition indicated by ↓ or ↑one high-level pulse
one low-level pulse
each output changes to the complement of its previous level on each active
transition indicated by ↓ or ↑In the input columns, if a row contains only the symbols H, L, or X, the indicated output is valid when the
input configuration is achieved, regardless of the sequence in which it is achieved. The output persists aslong as the input configuration is maintained.
In the input columns, if a row contains H, L, and/or X, together with ↑ and/or ↓, the output is valid when the
input configuration is achieved, but the transition(s) must occur after steady-state levels are attained. If theoutput is shown as a level (H, L, Q0, or Q0 ), it persists as long as the steady-state input levels and thelevels that terminate indicated transitions are maintained. Unless otherwise indicated, input transitions in
the opposite direction to those shown have no effect at the output. If the output is shown as a pulse, "-" ,or "- -", the pulse follows the indicated input transition and persists for an interval that is dependent on thecircuit.
Among the most complex function tables are those of the shift registers. These embody most of thesymbols used in any of the function tables, and more. Table 2 is the function table of a 4-bit bidirectional
universal shift register.
Table 2. Function Table
INPUTS
CLEAR
L

22

MODE
S1

S0

X

X

CLOCK

OUTPUTSSERIALPARALLEL

QA

QB

QC

QD

X

L

L

L

L
QD0

LEFT

RIGHT

A

B

C

D

X

X

X

X

X

X

H

X

X

L

X

X

X

X

X

X

QA0

QB0

QC0

H

H

H

↑

X

X

a

b

c

d

a

b

c

d

H

L

H

↑

X

H

H

H

H

H

H

QAn

QBn

QCn

H

L

H

↑

X

L

L

L

L

L

L

QAn

QBn

QCn

H

H

L

↑

H

X

X

X

X

X

QBn

QCn

QDn

H

H

H

L

↑

L

X

X

X

X

X

QBn

QCn

QDn

L

H

L

L

X

X

X

X

X

X

X

QA0

QB0

QC0

QD0

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The first row of the table represents a synchronous clearing of the register and states that, if clear is low,
all four outputs will be reset low, regardless of the other inputs, which are denoted by X. In the following
rows, clear is inactive (high); therefore, it has no effect.
The second row shows that, as long as the clock input remains low (while clear is high), no other input
has any effect, and the outputs maintain the levels they assumed before the steady-state combination ofclear high and clock low was established. Because, on other rows of the table only the rising transition of
the clock is shown to be active, the second row implicitly shows that no further change in the outputs
occurs while the clock remains high or on the high-to-low transition of the clock.
The third row of the table represents synchronous parallel loading of the register and states that if S1 andS0 are both high, then, without regard to the serial input, the data entered at A is at output QA, data
entered at B is at QB, and so forth, following a low-to-high clock transition.
The fourth and fifth rows represent the loading of high- and low-level data, respectively, from the shift-rightserial input and the shifting of previously entered data one bit; data previously at QA is now at QB, theprevious levels of QB and QC are now at QC and QD, respectively, and the data previously at QD no longer
is in the register. This entry of serial data and shift takes place on the low-to-high transition of the clock
when S1 is low and S0 is high, and the levels at inputs A through D have no effect.
The sixth and seventh rows represent the loading of high- and low-level data, respectively, from the shiftleft serial input and the shifting of previously entered data one bit; data previously at QB is now at QA, theprevious levels of QC and QD now are at QB and QC, respectively, and the data previously at QA no longer
is in the register. This entry of serial data and shift takes place on the low-to-high transition of the clock
when S1 is high and S0 is low, and the levels at inputs A through D have no effect.
The last row shows that, as long as both inputs are low, no other input has any effect and, as in thesecond row, the outputs maintain the levels they assumed before the steady-state combination of clear
high and both mode inputs low was established.
The function table functional tests do not reflect all possible combinations or sequential modes.
4.1.9

Logic Diagram
The logic diagram is a positive-logic illustration of the Boolean functionality of the device. Furthermore, insome logic-device data sheets that have wide identical configurations, such as a 16-bit or a 32-bit device,
the logic diagram often is shown in partial format that includes the unique circuitry and only one of thedata paths.
For D-type flip-flops and latches, it is TI convention to name the outputs and other inputs of a D-type flipflop or latch and to draw its logic symbol, based on the assumption of true data (D) inputs. Outputs that
produce data in phase with the data inputs are called Q, and those producing complementary data arecalled Q. An input that causes a Q output to go high or a Q output to go low is called preset (PRE). An
input that causes a Q output to go high or a Q output to go low is called clear (CLR). Bars are placed overthese pin names (PRE and CLR) if they are active low.
The devices on several data sheets are second-source designs, and the pin-name conventions used by
the original manufacturers have been retained. That makes it necessary to designate the inputs andoutputs of the inverting circuits, D and Q.
In some applications, it may be advantageous to re-designate the data input from D to D, or vice versa. In
that case, all the other inputs and outputs should be renamed, as shown Figure 27. Also shown, arecorresponding changes in the graphical symbols. Arbitrary pin numbers are shown.

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1
PRE

1
5

S

Q

2

C

C1

Q

C

C1
3

1D

D

6
Q

4
R

CLR

5

2

3
D

R

CLR

1D

6

4

Q

S

PRE
Latch

Latch

1
PRE

1
5

S

Q

2
C1

CLK

C1

CLK
3

1D

D

6
Q

4
CLR

Q

2

3
D

5

R

CLR

R

1D

6
Q

4
S

PRE
Flip-Flop

Flip-Flop
Copyright © 2016, Texas Instruments Incorporated

Figure 27. Example Logic Diagram
The figures show that when Q and Q exchange names, the preset and clear pins also exchange names.
The polarity indicators () on PRE and CLR remain, as these inputs still are active low, but thepresence or absence of the polarity indicator changes at D (or D), Q, and Q. Pin 5 (Q or Q) is still in phasewith the data input (D or D); their active levels change together.
4.1.10

Product Development Stage Note
The product development stage note is a standard disclaimer placed at the lower left corner of the firstpage of data sheets, and the words ADVANCED INFORMATION or PRODUCT PREVIEW, as applicable,
appear in the left and right margins of all pages of the data sheet. There is only the product development
stage note on the first page for production-data devices. For additional information, see the EIA/JEDEC
engineering publication, Suggested Product-Documentation Classifications and Disclaimers, JEP103A.

4.1.11

Table Of Contents
The Table of Contents section provides the outline for the data sheet with each section and a hyperlink
which when clicked to take directly to the specified page.

4.2

Revision History
The changes for the data sheet compared to previous revision is mentioned in a tabular format along withthe pages affected in the Revision History.

4.3

Pin Configuration And Functions
Each of the packages top view or the bottom view (whenever applicable) is shown along with a tabular
representation of the name of each pin , the pin position in each of the packages and the description ofeach pin. Each pin being input , output , Input /Output , power or ground pin is also mentioned in the sametable.

4.4
4.4.1

Absolute Maximum Ratings
Supply Voltage, VCC
This is the maximum voltage that can be applied safely to the VCC terminal, with respect to the ground of
the device. However, no data sheet parameters are ensured when a device is operated at the absolute
maximum VCC level.

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4.4.2

Input Voltage, VI
This is the maximum voltage that can be applied safely to an input terminal, with respect to the ground of
the device. This maximum VI specification may be exceeded if the output clamp rating, IIK, is observed.
Helpful Hint:
If there are clamp diodes between the device inputs and the VCC supply (see Figure 28) for ESD protection
or overshoot clamping, the positive absolute-maximum rating for the input voltage is specified as VCC + 0.5
V. Keeping the applied input voltage less than 0.5 V above VCC ensures that there will not be enoughvoltage across the clamp diode to forward-bias it and cause current to flow through it. The TI logic families
with clamp diodes in the inputs are: AC, ACT, AHC, AHCT, ALB, ALS, ALVC, AS, F, (CD)FCT, HC, HCT,
HSTL, LS, PCA, PCF, S, SSTL, and TTL.
If there are no clamp diodes between the device inputs and the VCC supply, the positive absolute
maximum rating is a limitation of the process technology and is specified as an absolute voltage (forexample, 5.5 V). The TI logic families without clamp diodes in the inputs are: ABT, ABTE, ALS, ALVT,
AUC, AVC, BCT, FB, GTLP, GTL, LS, LV, LVC, LVCZ, LVT, (CY)FCT, SSTV, and VME.
You may exceed the negative input-voltage rating if you ensure that you are not putting too much current
through the ground-clamp diode. The IIK absolute maximum rating specifies the maximum current that may
be put through the ground-clamp diode.
V CC

Power
Clamp

Power
Clamp

Logic

Input

OutputGroundClamp

GroundClamp

GND
Copyright © 2016, Texas Instruments Incorporated

Figure 28. Representation of Typical Logic I/O Clamping Circuits

4.4.3

Output Voltage, VO
This is the maximum voltage that can be applied safely to an output terminal, with respect to the ground of
the device.
Helpful Hint:
If there are clamp diodes between the device outputs and the VCC supply (see Figure 28) for ESD
protection or parasitic current paths in the output p-channel pullup transistor, the positive absolute
maximum rating for the output voltage is specified as VCC + 0.5 V. This ensures that there will not beenough voltage applied between the output and VCC to forward bias the clamp diode and cause current toflow. You may exceed the negative rating if you ensure that you are not putting too much current throughthe ground-clamp diode. The maximum current that you may put through the ground-clamp diode is
specified in the IOK absolute maximum rating.
If there are no clamp diodes or parasitic current paths in the output P-channel pullup transistor between
the device outputs and the VCC supply, the positive absolute maximum rating is a limitation of the process
technology and is specified as an absolute voltage.

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Dissecting the TI Logic Data Sheet

4.4.4

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Voltage Range Applied to Any Output in the High-Impedance or Power-Off State, V O
This specification is similar to the Output Voltage, VO specification and is used with the Voltage Range
Applied to Any Output in the High State, VO specification. On devices with the Ioff feature, there are noclamp diodes or parasitic current paths in the output P-channel pullup transistor between the device
outputs and the VCC supply; the positive absolute-maximum rating is a limitation of the process technology
and is specified as an absolute voltage. You may exceed the negative rating if you ensure that you are notputting too much current through the ground-clamp diode. The maximum current that you may put throughthe ground-clamp diode is specified in the IOK absolute-maximum rating.
Helpful Hint:
This specification is necessary only for devices with the Ioff feature.

4.4.5

Voltage Range Applied to Any Output in the High State, VO
This specification is similar to the Output Voltage, VO specification and is used with the Voltage Range
Applied to Any Output in the High-Impedance or Power-Off State, VO specification. When the output isenabled and is in the output high state, there is a current path between the output and VCC through theoutput P-channel pullup transistor. Applying a voltage to the output that is greater than the VCC voltage
causes damaging current to flow back from the output into the VCC supply. You may exceed the negative
rating if you ensure that you are not putting too much current through the power-clamp diode. The IOK
absolute-maximum rating specifies the maximum current that you may put through the ground-clamp
diode.
Helpful Hint:
This specification is necessary only for devices with the Ioff feature.

4.4.6

Input Clamp Current, IIK
This is the maximum current that can flow safely into an input terminal of the device at voltages above or
below the normal operating range.
Helpful Hint:
If there are clamp diodes between the device inputs and the VCC supply (see Figure 28), for ESD
protection or overshoot clamping, there will be both a positive and negative absolute maximum rating forthe input clamp current. If there is only a negative absolute maximum rating, that implies that there is onlya ground-clamp diode at the input, not a power-clamp diode.

4.4.7

Output Clamp Current, IOK
This is the maximum current that can flow safely into an output terminal of the device at voltages above or
below the normal operating range.
Helpful Hint:
If there are clamp diodes between the device outputs and the VCC supply (see Figure 28), for ESD
protection or parasitic current paths in the output P-channel pullup transistor, there will be both a positive
and a negative absolute-maximum rating for the output clamp current. If there is only a negative absolutemaximum rating, that implies that there is only a ground-clamp diode at the output, not a power-clamp
diode or a parasitic current path in the output P-channel pullup transistor.

4.4.8

Continuous Output Current, IO
This is the maximum output source or sink current that can flow safely into an output terminal of thedevice at voltages within the normal operating range.

4.4.9

Continuous Current Through VCC or GND Terminals
This is the maximum current that can flow safely into the VCC or GND terminals of the integrated circuit.

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4.4.10

Package Thermal Impedance, Junction-to-Ambient, ΘJAThis is the thermal resistance from the operating portion of a semiconductor device to a natural convection(still air) environment surrounding the device. Tested per JEDEC Standard JESD51-3. For additional
information, refer to the TI Application Report; Thermal Characteristics of Standard Linear and Logic (SLL)
Packages and Devices, literature number SCZA005.

4.4.11

Storage Temperature Range, Tstg
This is the range of temperatures over which a device can be stored without causing excessive
degradation of its performance characteristics. Typically, the junction temperature TJ is the same asstorage temperature.

4.5
4.5.1

Recommended Operating Conditions
VCC Supply Voltage
JEDEC - The supply voltage applied to a circuit connected to the reference terminal.
TI - The range of supply voltages for which operation of the logic element is specified.
The example in Figure 11 lists 2.7 V as the minimum VCC. No electrical or switching characteristic is
specified for VCC less than 2.7 V. Operation outside of the minimum and maximum values is notrecommended, and a previously established logic state might not be maintained under such conditions.
Helpful Hint:
Frequently, TI receives requests from customers wanting assurance that TI logic devices will operateproperly outside of specified conditions. The logic device may, indeed, perform flawlessly in the application
posed by the customer, but TI does not represent that the device will provide the same level of reliability
and performance when operated outside of specified conditions.

4.5.2

BIAS VCC Bias Supply Voltage
JEDEC - no definition offered
TI - A supply voltage used in generating a precharge voltage that is applied to an I/O for live-insertion
purposes.
Power sequencing is critical in live-insertion applications. Therefore, care must be taken with the timing of
application of BIAS VCC, VCC, ground, and data input voltages during an insertion or extraction of adaughter card implementing a device with this capability (see the application report, Logic in Live-Insertion
Applications With a Focus on GTLP, literature number SCEA026).
Helpful Hint:
Texas Instruments offers only three technologies with true live-insertion capabilities: FB, GTLP, and VME.

4.5.3

VTT Termination Voltage
JEDEC - no definition offered
TI - A supply voltage used to terminate a bus (most commonly used in open-drain devices) and ingenerating a reference voltage for differential inputs.
Because open-drain devices such as GTLP and FB cannot raise the output voltage to a high state by theirown accord, external resistors, which are tied to an external termination voltage, are used.
Helpful Hint:
VTT determines the high-level voltage value and, since most open-drain technologies can tolerate a wide
range of voltage levels, open-drain devices are used quite often in voltage-translation applications.

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Dissecting the TI Logic Data Sheet

4.5.4

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Vref Reference Voltage
JEDEC - A power supply that acts as a reference for determining internal threshold voltages, but does not
supply any substantial power to the device.
TI - A reference bias voltage used to set the switching threshold of differential input devices.

4.5.5

VIH High-Level Input Voltage
JEDEC - VIH min is the least positive (most negative) value of high-level input voltage for which operationof the logic element within specification limits is to be expected. VIH max is the most positive (least
negative) value of high-level input voltage for which operation of the logic element within specification
limits is to be expected.
TI - An input voltage within the more positive (the less negative) of the two ranges of values used torepresent the binary variables.
NOTE: A minimum is specified that is the least positive value of high-level input voltage for which
operation of the logic element within specification limits is to be expected.

A voltage within this range corresponds to the logic-1 state in positive logic. During device testing, VIH minis specified for all inputs. Since VIH min is used to set up VOH, VOL, IOZH, and IOZL tests, all possiblecombinations of input thresholds may not be verified. The non-data inputs (for example, direction, clear,enable, and preset) may be considered unused inputs and may not be at threshold conditions. These
inputs control functions that can cause all the outputs to switch simultaneously. The noise that can begenerated by switching a majority of the outputs at one time can cause significant tester ground and VCC
movement. This can result in false test measurements.
Helpful Hint:
Some bipolar-input devices sink a certain amount of current into the input pin, as specified on the data
sheet. The higher the VIH voltage is, the more current that will be drawn into the input pin. CMOS-input
devices behave in a different manner because, in most cases, the input pin essentially is tied directly tothe high-impedance gate of an input inverter. In a static dc state, a CMOS input sinks or sources only aminute amount of leakage current (a few µA). However, it is imperative that for any logic device, but
especially for a CMOS input, the input high logic level always be above the recommended VIH min. Failure
to do this causes a surge of current to flow through the input inverter from the VCC supply to ground and,
subsequently, may destroy the device.
Helpful Hint:
TI data sheets do not specify a VIH max that typically is found in competitor data sheets. Instead, see VI
max for the same value.
Helpful Hint:
Failure to supply a voltage to the input of a CMOS device that meets the VIH or VIL recommended
operating conditions can cause: (1) propagation of incorrect logic states, (2) high ICC currents, (3) highinput noise gain and oscillations, (4) power- and ground-rail surge currents and noise, and (5) catastrophic
device and circuit failure.
Helpful Hint:
A device with an input VIH = 2 V and a VIL = 0.8 V has a TTL-compatible input. A device with the input
levels scaled with respect to VCC (for example, VIH = 0.7 × VCC, VIL = 0.3 × VCC) has CMOS inputs.
4.5.6

VIL Low-level Input Voltage
JEDEC - VIL min is the least-positive (most negative) value of low-level input voltage for which operation of
the logic element within specification limits is to be expected. VIL max is the most positive (least negative)
value of low-level input voltage for which operation of the logic element within specification limits is to be
expected.
TI - An input voltage within the less positive (more negative) of the two ranges of values used to represent
the binary variables.

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NOTE: A maximum is specified that is the most-positive value of low-level input voltage for which
operation of the logic element within specification limits is to be expected.

A voltage within this range corresponds to the logic-0 state in positive logic. During device testing, VIL max
is specified for all inputs. Because VIL max is used to set up VOH, VOL, IOZH, and IOZL tests, all possiblecombinations of input thresholds may not be verified. The non-data inputs (for example, direction, clear,enable, and preset) may be considered unused inputs and may not be at threshold conditions. These
inputs control functions that can cause all the outputs to switch simultaneously. The noise that can begenerated by switching a majority of the outputs at one time can cause significant tester ground and VCCchanges. This can result in false test measurements.
Helpful Hint:
Most bipolar-input devices source a certain amount of current out of the input pin, as specified on the data
sheet. The lower the VIL voltage is, the more current that will be drawn out of the input pin. CMOS-input
devices behave in a different manner because, in most cases, the input pin essentially is tied directly to
the gate of an input inverter. In a static dc state, a CMOS input sinks or sources only a minute amount ofleakage current (a few µA). However, it is imperative that for any logic device, but especially for a CMOS
input, the input low logic level always be below the recommended VIL max.
CAUTION
Failure to do this will cause a surge of current to flow through the input inverter
from the VCC supply to ground and, subsequently, may destroy the device.
Helpful Hint:
TI data sheets do not specify a VIL min that typically is found in competitor data sheets. Instead, see VI
min for the same value.
Helpful Hint:
Failure to supply a voltage to the input of a CMOS device that meets the VIH or VIL recommended
operating conditions can cause: (1) propagation of incorrect logic states, (2) high ICC currents, (3) highinput noise gain and oscillations, (4) power- and ground-rail surge currents and noise, and (5) catastrophic
device and circuit failure.
Helpful Hint:
A device with an input VIH = 2 V and a VIL = 0.8 V has a TTL-compatible input. A device with the input
levels scaled with respect to VCC (for example, VIH = 0.7 × VCC, VIL = 0.3 × VCC) has CMOS inputs.
4.5.7

IOH High-Level Output Current
JEDEC - The current into the output terminal with input conditions applied that, according to the productspecification, establishes a high level at the output.
TI - The current into an output with input conditions applied that, according to the product specification,
establishes a high level at the output.
TI data sheets specify currents flowing out of a device as a negative value. IOH max is used as a test
condition for VOH. See VOH testing for further details.
Logic output drivers have a maximum current drive capability that they can source and still be able tosustain a valid logic-high level. In a static dc state, where current is drawn continuously from the output,
because CMOS drivers operate in the linear region, their behavior is somewhat like a low-impedance
resistor and increases in voltage potential (that is, decreases the VOH level) as the increasing current issourced out of the output pin during a VOH test. Consequently, a TI logic device operates with a high-level
output current that is above the recommended operating range (but below the absolute maximum rating),
but TI does NOT represent that the device can sustain the specified VOH level or that the device will
operate without any reliability concerns.

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4.5.8

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IOHS Static High-Level Output Current
JEDEC - no definition offered
TI - The static and testable current into a Dynamic Output Control (DOC™ circuitry) output with input
conditions applied that, according to the product specifications, establishes a static high level at theoutput. The dynamic drive current is not specified for devices with DOC circuitry outputs because of its
transient nature; however, it is similar to the dynamic drive current that is available from a high-drive(nondamping resistor) standard-output device.
TI data sheets specify currents flowing out of a device as a negative value.
DOC circuitry is designed to drive CMOS input devices, which are capacitive in nature, in point-to-point
applications (one receiver input per driver output). For this reason, a large static high-level output current
is not required. In this case, what matters most is the high transient-drive capability of the output.
For additional information about DOC circuitry, refer to the TI application report, Dynamic Output Control(DOC™) Circuitry Technology and Applications, literature number SCEA009.

4.5.9

IOL Low-Level Output Current
JEDEC - The current into the output terminal with input conditions applied that, according to the productspecification, will establish a low level at the output.
TI - The current into an output with input conditions applied that, according to the product specification,
establishes a low level at the output.
TI data sheets specify currents flowing out of a device as a negative value. IOL maximum is used as a test
condition for VOL. See VOL testing for details.
Logic output drivers have a maximum current-drive capability that they can sink and still be able to sustain
a valid logic-low level. In a static dc state where current is continuously drawn into the output, because
CMOS drivers operate in the linear region, their behavior will be somewhat like a low-impedance resistor
and will increase in voltage potential (that is, increase the VOL level) as the increasing current is sunk into
the output pin during a VOL test. Consequently, a TI logic device will operate with a low-level output current
that is above the recommended operating range (but below the absolute maximum rating), but TI does
NOT represent that the device can sustain the specified VOL level or that the device will operate without
any reliability concerns.

4.5.10IOLS Static Low-Level Output Current
JEDEC - no definition offered
TI - The static and testable current into a Dynamic Output Control (DOC circuitry) output with input
conditions applied that, according to the product specifications, establishes a static low level at the output.
The dynamic drive current is not specified for devices with DOC circuitry outputs because of its transient
nature; however, it is similar to the dynamic drive current that is available from a high-drive (nondamping
resistor) standard-output device.
TI data sheets specify currents flowing out of a device as a negative value.
DOC circuitry is designed to drive CMOS input devices, which are capacitive in nature, in point-to-point
applications (one receiver input per driver output). For this reason, a large static low-level output current is
not required. What matters most in this case is the high-transient-drive capability of the output.
For additional information about DOC circuitry, refer to the TI application report, Dynamic Output Control(DOC™) Circuitry Technology and Applications, literature number SCEA009.

4.5.11

VI Input Voltage
JEDEC - The voltage at the input terminals.
TI - The range of input voltage levels over which the logic element is specified to operate.
VI min and VI max values are used as test conditions for the II, ICC, ΔlCC, Ci, and Cio test. See thosespecifications for details.

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Helpful Hint:
If there are clamp diodes between the device inputs and the VCC supply (see Figure 28) for ESD protection
or overshoot clamping, the positive absolute maximum rating for the input voltage will be specified as VCC+ 0.5 V. Keeping the applied input voltage less than 0.5 V above VCC ensures that there will not be enoughvoltage across the clamp diode to forward bias it and cause current to flow through it.
You may exceed the negative rating if you ensure that you are not putting too much current through theground-clamp diode. The maximum current that you may put through the ground-clamp diode is specified
in the IIK absolute-maximum rating.
Helpful Hint:
This parameter provides a means to determine if the device is tolerant of a higher voltage than the supply
voltage. If the input is overvoltage tolerant, the positive maximum rating for the input voltage will be an
absolute voltage rating (for example, 5.5 V) and will be limited by the capabilities of the wafer-fab process.
For example, the LVC technology is specified to operate at a voltage supply no higher than 3.6 V.
However, the input voltage is recommended to be 5.5 V maximum. This indirectly states that the device is
a 5-V tolerant device. The same can be said about AUC devices because the maximum supply voltage is
2.7 V, whereas the maximum input voltage is 3.6 V, making this technology 3.3-V tolerant.
Helpful Hint:
This parameter explicitly states the recommended minimum and maximum input voltage levels for any
input. While the VI specification typically spans the range from below ground to above VCC, failure tosupply a voltage to the input of a CMOS device that meets the VIH or VIL recommended operating
conditions can cause: (1) propagation of incorrect logic states, (2) high ICC currents, (3) high input noise
gain and oscillations, (4) power- and ground-rail surge currents and noise, and (5) catastrophic device andcircuit failure.
4.5.12VO Output Voltage
JEDEC - The voltage at the output terminals.
TI - The range of output voltage levels over which the logic element is specified.
VO minimum and maximum values are used as test conditions for IOZH and IOZL. See these tests for details.
Helpful Hint:
The load at the output strictly determines the output voltage. As discussed in the VOH and VOL descriptions,a constant dc current decreases and increases, respectively, the output voltage. For this reason, TI does
not recommend to drive bipolar inputs with CMOS outputs unless the sum of all bipolar input current isless than the rated IOH and IOL of the CMOS output. Highly capacitive loads, such as any CMOS type input,
will not incur any static dc current, so a CMOS output voltage should be close to the rail when asserted
high or low. Capacitive loads, not the ultimate static dc voltage level, determine the time it takes for the
output to arrive at the logic high or low state.

4.5.13Δt/Δv Input Transition Rise or Fall RateJEDEC - no definition offered
TI - The rate of change of the input voltage waveform during a logic transition (low-to-high or high-to-low).
To avoid output-waveform abnormalities, input voltage transitions should be within the range set forth in
the recommended operating conditions.
Customers often place external capacitors on a trace to ensure the driver does not switch rapidly from one
logic state to another. This is sometimes done to prevent unwanted overshoot and undershoot voltage
conditions that could cause ringing and degrade signal integrity, or in switch debounce circuits. However,this could cause problems at the input; therefore, TI provides input transition rise or fall rates. The problem
may not arise due to external capacitive loading, however, but may be the result of choosing a device witha weak driver. In either case, the end result is a voltage waveform that is too slow for the device.

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Slow transition rates wreak havoc on CMOS inputs because a slowly changing input voltage will induce alarge amount of current from the power supply to ground. This phenomenon is known as through current.
Through currents are normal ac transient currents, but when they are sustained indefinitely-as are thosecaused by slow input transition rates-the device will not perform as expected, and its output voltage may
oscillate or, even worse, damage the device. This surge of current, if large enough, will disturb the groundreference because of the inductive nature of the package [V = L × (di/dt)] and produce a positive-going
glitch on the ground reference. The glitch may, in turn, reduce the relative magnitude, causing the output
node of the input inverter to switch states. Ultimately, this erroneous data propagates to the output of thedevice, thereby causing oscillations. The more inputs that are being switched in the same manner, theworse this condition becomes, as more current is being forced into ground during a short time. TI data
sheets specify the slowest input transition rate to avoid this problem. For additional information, refer tothe TI application report, Implications of Slow or Floating CMOS Inputs, literature number SCBA004.
Helpful Hint:
If you must supply a slowly changing voltage to the input of a logic device, select a device that has
Schmitt-trigger inputs. These inputs have been specifically designed to tolerate slow edges. An example ofsuch a device in the LVC family is the SN74LVC14A.
4.5.14Δt/ΔVCC Power-up Ramp RateJEDEC - no definition offered
TI - The rate of change of the supply voltage waveform during power up.

4.5.15TA Operating Free-Air Temperature
JEDEC - no definition offered
TI - The range of operating temperatures over which the logic element is specified.
In digital-system design, consideration must be given to thermal management of components. The small
size of packages makes this more critical. Figure 36 shows the high-effect (high-K) thermal resistance forthe 5-, 14-, 16-, 20-, 24-, 48-, 56-, 64-, and 80-pin packages for various rates of airflow calculated inaccordance with JESD51-7.
The thermal resistance in Figure 36 can be used to approximate typical and maximum virtual junction
temperatures. In general, the junction temperature for any device can be calculated using the following
equation:
TJ = RΘJA× PT + TA

where
•
•
•
•

TJ = virtual junction temperature (°C)
RΘJA = thermal resistance junction to free air (°C/W)
PT = total power dissipation of the device (W)TA = free-air temperature (°C)(1)

More additional information on all the thermal metrics used for integrated circuit refer to the TI application
report , Semiconductor and IC package Thermal Metrics ,SPRA953.

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Dissecting the TI Logic Data Sheet

DCK

240
220
200
180

DBV

160
140
120
100
80
60
40

–

20
0

R JA – Junction-to-Ambient Thermal Resistance - °C/W

260

130
120
110

0

100

200

300

400

500

DGV
PW

100

θ

θ

R JA – Junction-to-Ambient Thermal Resistance - °C/W

www.ti.com

90
80

DB

70

D

60
50
40
30
20
10
0
0

DGV
PW

80
DB
D

60
50
40
30
20
10
0
0

100

200

300

400

500

Air Velocity – ft/min
Figure 31. JUNCTION-TO-AMBIENT THERMALRESISTANCE vs Air Velocity

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R JA – Junction-to-Ambient Thermal Resistance - °C/W

110

θ

θ

R JA – Junction-to-Ambient Thermal Resistance - °C/W

120

70

300

400

500

Figure 30. JUNCTION-TO-AMBIENT THERMALRESISTANCE vs Air Velocity

130

90

200

Air Velocity – ft/min

Air Velocity – ft/min
Figure 29. JUNCTION-TO-AMBIENT THERMALRESISTANCE vs Air Velocity

100

100

130
120
110
100
90
80
70

DGV
PW

60

DB

50
DW

40
30
20
10
0
0

100

200

300

400

500

Air Velocity – ft/min
Figure 32. JUNCTION-TO-AMBIENT THERMALRESISTANCE vs Air Velocity

Understanding and Interpreting Standard-Logic Data Sheets

Copyright © 2002–2016, Texas Instruments Incorporated

33

130
120
110
100
90
80

PW
DGV

70
60

DB

50
40

DW

30
20
10
0
0

100

200

300

400

500

R JA – Junction-to-Ambient Thermal Resistance - °C/W

www.ti.com

θθR JA – Junction-to-Ambient Thermal Resistance -°C/W

Dissecting the TI Logic Data Sheet
190
180
170
160
150
140
130
120
110
100
90
80
70

DGG
DL
DGV

60
50
40
30
0

300

400

500

JUNCTION-TO-AMBIENT THERMAL RESISTANCE
vsAIR VELOCITY

65
60
55

DGG

50
45
DL

40

DGV

35
30
25
20
15
10
5
0
0

100

200

300

400

500

Air Velocity – ft/minθFigure 35. JUNCTION-TO-AMBIENT THERMALRESISTANCE vs Air Velocity

34

200

Air Velocity – ft/min
Figure 34. JUNCTION-TO-AMBIENT THERMALRESISTANCE vs Air Velocity

R JA –Junction-to-Ambient Thermal Resistance - °C/W

θ

R JA – Junction-to-Ambient Thermal Resistance - °C/W

Air Velocity – ft/min
Figure 33. JUNCTION-TO-AMBIENT THERMALRESISTANCE vs Air Velocity

100

Understanding and Interpreting Standard-Logic Data Sheets

64-Pin Packages
65
60
55
50
DGG

45
40
35
30
25
20
15
10
5
0
0

100

200

300

400

500

Air Velocity – ft/min
Figure 36. High-K Thermal-Resistance Images for 5-, 14-,16-, 20-, 24-, 48-, 56-, 64-, and 80-Pin Packages

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80-Pin Packages
65
60
55
50

DBB

45
40
35
30
25
20
15
10

θ

R JA – Junction-to-Ambient Thermal Resistance – °C/W

JUNCTION-TO-AMBIENT THERMAL RESISTANCE
vsAIR VELOCITY

5
0
0

100

200

300

400

500

Air Velocity – ft/min
Figure 37. High-K Thermal-Resistance Images for 5-, 14-, 16-, 20-, 24-, 48-, 56-, 64-, and 80-Pin Packages (Continued)

4.6
4.6.1

Electrical Characteristics
VT+ Positive-Going Input Threshold Level
JEDEC - The input threshold voltage when the input voltage is rising.
TI - The voltage level at a transition-operated input that causes operation of the logic element, according
to specification, as the input voltage rises from a level below the negative-going threshold voltage, VT-.
See Section 4.6.3, ΔVT Hysteresis (VT+ - VT-), for further information.

4.6.2

VT- Negative-Going Input Threshold Level
JEDEC - The input threshold voltage when the input voltage is falling.
TI - The voltage level at a transition-operated input that causes operation of the logic element according to
specification, as the input voltage falls from a level above the positive-going threshold voltage, VT+.
See Section 4.6.3, ΔVT Hysteresis (VT+ - VT-), for further information.

4.6.3

ΔVT Hysteresis (VT+ - VT-)JEDEC - The difference between the positive-going and negative-going input threshold voltages.
TI - Refer to the JEDEC definition above.
Hysteresis has been incorporated into logic devices for many years and exists in bipolar as well as CMOS
circuitry. Although the circuitry is different, the implementation is the same: the input voltage threshold
actually changes internally from one level to another, as the input logic level itself switches. Figure 38 is
the most common voltage plot for the input and output, as the input transitions from one logic state to theother. Figure 39, however, shows VIT+ and VIT- in a voltage versus time waveform.

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Output Voltage

VOH

∆ VT

VOL

VT–

VT+
Input Voltage
Copyright © 2016, Texas Instruments Incorporated

Figure 38. Hysteresis: VI vs VO

V IH

Input Voltage

V T+
∆V T
V T–

V IL

Time

Immediately
switches input
threshold to VT–

Immediately
switches input
threshold to VT+

after low-to-hightransition

after high-to-lowtransition

Figure 39. Hysteresis: Input Voltage vs TimeThe benefit of a device that has built-in dc hysteresis is that, depending on the amount of hysteresis andthe amount of noise present, the input is immune to such noise. This digital form of filtering out unwanted
noise can be beneficial in a system where noise caused by electromagnetic interference (EMI) or crosstalkcannot be reduced. Figure 40 and Figure 41 conceptually depict the functionality of hysteresis.

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Input
VThreshold

OutputTime

Glitches are propagatedthrough the device.

Voltage

Figure 40. Possible Output-Voltage Outcome for Devices Without Hysteresis

V T+
Input

V T–

OutputTime

No glitches present

Figure 41. Glitch-Rejection Capabilities of Devices With Hysteresis

4.6.4

VIK Input Clamp Voltage
JEDEC - An input voltage in a region of relatively low differential resistance that serves to limit the voltage
swing.
TI - The maximum voltage developed across an input diode with test current applied.

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Helpful Hint:
The presence of a VIK specification indicates that there is a ground-clamp diode on the input and the V-I
characteristics of that diode in its forward-biased region are given.
4.6.5

VOH High-Level Output Voltage
JEDEC - The voltage level at an output terminal with input conditions applied that, according to the
product specification, will establish a high level at the output.
TI - The voltage level at an output terminal with input conditions applied that, according to the productspecification, establishes a high level at the output.
VOH is tested with input conditions that should cause the output under test to be at a high-level voltage.
The output then is forced to source the required current, as defined in the data sheet, and the output
voltage is measured. The test is passed if the voltage is greater than VOH min. The input voltage levels
used to precondition the device are VIL max and VIH min, as defined in the Recommended Operating
Conditions. See Section 4.5.7, IOH High-Level Output Current, for further information.
Helpful Hint:
Inclusion of a VOH specification with a test condition of IOH = –100 µA is done primarily to indicate that thedevice has CMOS outputs instead of bipolar (npn or pnp) drivers. Bipolar output transistors typically are
not able to swing the output voltages all the way to the power-supply rail or ground rail, even under noload or lightly loaded conditions. If a device has bipolar outputs, this test condition would not apply and is
not included in the data sheet. If you see this specification, you can safely assume the outputs to be of
CMOS construction.

4.6.6

VOHS Static High-Level Output Voltage
JEDEC - no definition offered
TI - The static and testable voltage at a Dynamic Output Control (DOC circuitry) output with input
conditions applied that, according to the product specifications, establishes a static high level at theoutput. The dynamic drive voltage is not specified for devices with DOC circuitry outputs because of its
transient nature.
See Section 4.5.8, IOHS Static High-Level Output Current, for further information.
For additional information about DOC circuitry, refer to the TI application report, Dynamic Output Control(DOC™) Circuitry Technology and Applications, literature number SCEA009.

4.6.7

VOL Low-Level Output Voltage
JEDEC - The voltage level at an output terminal with input conditions applied that, according to the
product specification, will establish a low level at the output.
TI - The voltage level at an output terminal with input conditions applied that, according to the productspecification, establishes a low level at the output.
VOL is tested with input conditions that should cause the output under test to be at a low level. The output
then is forced to sink the required current, as defined in the data sheet, and the output voltage ismeasured. The test is passed if the voltage is less than VOL max. The input voltage levels used toprecondition the device are VIL max and VIH min, as defined in the recommended operating conditions.
See Section 4.5.9, IOL Low-Level Output Current, for further information.
Helpful Hint:
Inclusion of a VOL specification with a test condition of IOL = 100 µA is done primarily to indicate that thedevice has CMOS outputs instead of bipolar (npn or pnp) drivers. Bipolar output transistors typically are
not able to swing the output voltages all the way to the power-supply rail or ground rail, even under noload or lightly loaded conditions. If the outputs were bipolar, this test condition would not apply and is notincluded in the data sheet. If you see this specification, you can safely assume the outputs to be of CMOS
construction.

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4.6.8

VOLS Static Low-Level Output Voltage
JEDEC - no definition offered
TI - The static and testable voltage at a Dynamic Output Control (DOC circuitry) output with input
conditions applied that, according to the product specifications, establishes a static low level at the output.
The dynamic drive voltage is not specified for devices with DOC circuitry outputs because of its transient
nature.
See Section 4.5.10, IOLS Static Low-level Output Current, for further information.
For additional information about DOC circuitry, refer to the TI application report, Dynamic Output Control(DOC™) Circuitry Technology and Applications, literature number SCEA009.

4.6.9

ron On-State Resistance
JEDEC - The resistance between specified terminals with input conditions applied that, according to the
product specification, will establish minimum resistance (the on-state) between those terminals.
TI - The resistance measured across the channel drain and source (or input and output) of a bus-switch
device.

4.6.10Peak On-State Resistance
TI - The highest resistance measured across the drain and source channels of switch across the valid
input range of operation.

4.6.11

Delta On-State Resistance
TI -The difference between the on-state resistance between any 2 channels of the switch.

4.6.12II Input Current
JEDEC - The current at the input terminals.
TI - The current into an input (current into a terminal is given as a positive value).
Helpful Hint:
CMOS inputs sink or source only minute amounts of current (commonly called leakage current) becauseof the behavior of standard CMOS technology, which is voltage controlled instead of current controlled. As
a result, this parameter always should have a maximum specification no greater than a few tens of micro
amperes. For most bipolar inputs, which are current controlled instead of voltage controlled, a large
amount of current is normal (a few milliamperes). In fact, a good method to determine if a device has a
CMOS input is to examine its maximum input current specification: if this current is approximately thevalue of leakage current, typically, this means that it is a CMOS input.
Helpful Hint:
For the data signals of a device without bus-hold, the II specification includes both input and output
leakage currents at the I/O pin. For devices that have bus-hold on the data signals, the II specification
should apply only to the control inputs because the bus-hold output supplies enough current to overcome
any internal input leakage.
An exception to this is an II specification for an overvoltage-tolerant bus-hold input with a test condition of
VI >> VCC. This is used to indicate that the overvoltage-tolerant bus-hold output has a Schottky blocking
diode in series with the output p-channel pullup transistor to VCC, which prevents current from flowing fromthe output back into the VCC supply. See II(hold) and Ioff for more information.

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IIH High-Level Input Current
JEDEC - The current into an input terminal when a specified high-level voltage is applied to that input.
TI - The current into an input when a high-level voltage is applied to that input.
Helpful Hint:
IIH and IIL typically are found only on devices with bipolar inputs that usually require a significantly different
amount of pulldown current on the input to provide a logic low, rather than pullup current to provide a logic
high. CMOS inputs usually have only leakage currents at the inputs and use the II parameter, but aremeasured at both low- and high-bias conditions.

4.6.14

IIL Low-Level Input Current
JEDEC - The current into an input terminal when a specified low-level voltage is applied to that input.
TI - The current out of an input when a low-level voltage is applied to that input.
Helpful Hint:
IIH and IIL typically are found only on devices with bipolar inputs that usually require a significantly different
amount of pulldown current on the input to provide a logic low, rather than pullup current to provide a logic
high. CMOS inputs usually have only leakage currents at the inputs and use the II parameter.

4.6.15II(hold) Input Hold Current
JEDEC - no definition offered
TI - The input current that holds the input at the previous state when the driving device goes to the highimpedance state.
For additional information about the bus-hold feature, refer to the TI application report, Bus-Hold Circuit,
literature number SCLA015.
Older technologies, such as ABT, LVT, LVC and ALVC (on devices that have the H option), specify thisparameter. This parameter is measured with the minimum VCC and an input bias voltage that is at VIH min
and VIL max of the particular input threshold. For example, the ALVC family has a specified VIL max of 0.7
V for a VCC ranging from 2.3 V to 2.7 V, whereas its VIH min is 1.7 V for the same supply voltage. Within a
VCC range of 2.7 V to 3.6 V, the input threshold for the ALVC family is VIH min = 2 V and VIL max = 0.8 V.
Therefore, with VCC = 2.3 V, II(hold) is measured with the input voltage set to 0.7 V and 1.7 V. With a VCC =2.7 V (minimum VCC of 2.3 V to 2.7 V), II(hold) is measured with the input voltage set to 0.8 V and 2 V. This
specification explicitly states the minimum amount of current the input structure sources or sinks, with
input voltages set to the minimum threshold requirements of the device.
Another parameter that may be included with this II(hold) specification is the maximum current the device
can sink or source as the input transitions from one logic state to another. This maximum current is theminimum amount of drive capability that must be provided by the driver that is connected to this bus-holdinput to switch the input stage to the other logic state. In newer technologies such as AVC, the parameters
IBHH, IBHL, IBHHO, and IBHLO have been defined with their own separate specifications, but are identical innature to those that are lumped with the II(hold) parameter. Figure 42 is a representation of these bus-holdcurrent measurements.
Helpful Hint:
The II(hold) specification is not used in recent data sheets; instead, IBHH, IBHL, IBHHO, and IBHLO are used.

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I BHLO

Input threshold voltage
with VCCmax

Input Current - mA

I BHL

VCCmin

VCCmax

VIHmin0V

Input Voltage - V

VILmaxInput threshold voltage
with V CC min
I BHH

I BHHO

Figure 42. Bus-Hold Currents

4.6.16

IBHH Bus-Hold High Sustaining Current
JEDEC - no definition offered
TI - The bus-hold circuit can source at least the minimum high sustaining current at VIH min. IBHH should bemeasured after raising the input voltage to VCC, then lowering it to VIH min.
For additional information about the bus-hold feature, refer to the TI application report, Bus-Hold Circuit,
literature number SCLA015. Also, see Section 4.6.15, II(hold) Input Hold Current, for further information.

4.6.17

IBHL Bus-Hold Low Sustaining Current
JEDEC - no definition offered
TI - The bus-hold circuit can sink at least the minimum low sustaining current at VIL max. IBHL should bemeasured after lowering the input voltage to GND and raising it to VIL max.
For additional information about the bus-hold feature, refer to the TI application report, Bus-Hold Circuit,
literature number SCLA015. Also, see Section 4.6.15, II(hold) Input Hold Current, for further information.

4.6.18IBHHO Bus-Hold High Overdrive Current
JEDEC - no definition offered
TI - The current that an external driver must sink to switch this node from high to low.
For additional information about the bus-hold feature, refer to the TI application report, Bus-Hold Circuit,
literature number SCLA015. Also, see Section 4.6.15, II(hold) Input Hold Current, for further information.

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IBHLO Bus-Hold Low Overdrive Current
JEDEC - no definition offered
TI - The current that an external driver must source to switch this node from low to high.
For additional information about the bus-hold feature, refer to the TI application report, Bus-Hold Circuit,
literature number SCLA015. Also, Section 4.6.15 for further information.

4.6.20

Ioff Input/Output Power-Off Leakage Current
JEDEC - The current into a circuit node when the device or a portion of the device affecting that circuit
node is in the off state.
TI - The maximum leakage current into an input or output terminal of the device, with the specified voltage
applied to the terminal and VCC = 0 V.
The Ioff protection circuitry ensures that no excessive current is drawn from or to an input, output, or
combined I/O that is biased to a specified voltage while the device is powered down, and is said tosupport partial-power-down mode of system operation. This condition can occur when subsections of asystem are powered down (partial power down) to reduce power consumption. The TI logic families with
the Ioff feature that support partial power down are: AVC, LV, LVC, (CY)FCT, GTL, LS, ALS, and AUC.
All TI standard logic devices with Ioff allow a maximum of approximately 100 µA to flow under these
conditions. Any current in excess of this amount (a pn junction, for example, being forward biased) is notconsidered normal leakage current. Inherent in all CMOS designs are the parasitic diodes in all N-channel
and P-channel FETs, which must be properly biased to prevent unwanted current paths. The output
structure of a typical CMOS output is shown in Figure 43.
VCC
Upper
p-channel

VCC

Parasitic
Diode

Blocking
Diode

Parasitic
Diode

From
Internal
Logic

Out
Parasitic
Diode

Lower
n-channel

Parasitic
Diode

Copyright © 2016, Texas Instruments Incorporated

Figure 43. Typical CMOS Totem-Pole Output With Ioff
The common cathode connection for the parasitic diodes on the p-channel MOS transistor is called theback gate and, typically, is tied to the highest potential on the device (VCC, in the case of TI logic devices).
For P-channel transistors, which are directly connected to external pins, the back gate is blocked with adiode to prevent excess currents flowing from the external pin to the supply-voltage VCC when the output
voltage is greater than VCC by at least 0.7 V. This blocking diode is a subcircuit of the complete Ioff circuitry
found in several logic families, such as ABT and LVC. The other portion of the Ioff circuit is not shown, butis, essentially, added FET circuitry that prevents the upper output P-channel from turning on during apartial-power-down event. The output N-channel, however, does not pose a problem because the parasitic
diode already blocks current when the device is powered down and the output is biased high.
Figure 44 shows a typical CMOS input structure with bus-hold circuitry, which is essentially a weak latchthat holds the previous state of the input inverter. The blocking diode is, again, required in the upper pchannel transistor that is connected to the external input pin. A non-bus-hold device does not require a
blocking diode, as there is no p-channel source or drain connected to an external pin.

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VCC

VCC

Blocking
Diode
Parasitic
Diode
Parasitic
Diode

To
Internal
Logic
Copyright © 2016, Texas Instruments IncorporatedIN

Figure 44. Typical CMOS Input With Bus-Hold and Ioff
4.6.21IOZ Off-State (High-Impedance State) Output Current (of a 3-State Output)
JEDEC - no definition offered
TI - The current flowing into an output with the input conditions applied that, according to the productspecification, establishes the high-impedance state at the output
TI data sheets specify currents flowing out of a device as a negative value.
The electrical characteristic, IOZ, is verified utilizing the IOZH and IOZL tests. Two tests are required to verify
the integrity of both the P- and N-channel transistors.
Helpful Hint:
For bidirectional (transceiver) devices that have bus hold on the data input/output pins, there should not
be an IOZ specification because the bus-hold output supplies enough current to overcome any internal
output leakage.
An exception to this is an IOZH specification for an overvoltage-tolerant bus-hold output with a test conditionof VO >> VCC. This is used to indicate that the overvoltage-tolerant bus-hold output has a Schottky blocking
diode in series with the output p-channel pullup transistor to VCC and Ioff circuitry, preventing the upper Pchannel from turning on, which prevents current from flowing from the output back into the VCC supply.
See II(hold) and Ioff for more information.

4.6.22IOZH Off-State Output Current With High-Level Voltage Applied
JEDEC - no definition offered
TI - The current flowing into a 3-state output with input conditions established that, according to the
product specification, will establish the high-impedance state at the output with a high-level voltage applied
to the output.
This parameter is measured with other input conditions established that would cause the output to be at alow level if it were enabled. IOZH is tested by applying the specified voltage to the output and measuring thecurrent into the device with the output in the high-impedance state. Input conditions that would establish a
low level on the output if it were enabled areVIL = VIL max and VIH = VIH min. Each output is tested
individually. For example, the unused inputs are at VIL = 0 or VIH = VCC for AC devices and VIL = 0 or VIH =3 V for ACT devices, depending on the desired state of the outputs not being tested.
Helpful Hint:
An IOZH specification on bidirectional (transceiver) devices with bus hold on the data input/output pins, witha test condition of VO >> VCC, indicates that the overvoltage-tolerant bus-hold output has a Schottky
blocking diode in series with the output P-channel pullup transistor to VCC. This diode prevents current
flowing from the output back into the VCC supply. See II(hold) and Ioff for more information.

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IOZL Off-State Output Current With Low-Level Voltage Applied
JEDEC - no definition offered
TI - The current flowing into a 3-state output with input conditions established that, according to the
product specification, will establish the high-impedance state at the output, with a low-level voltage applied
to the output.
This parameter is measured with other input conditions established that would cause the output to be at ahigh level if it were enabled. IOZL is tested by applying the specified voltage to the output and measuring
the current into the device with the output in the high-impedance state. Input conditions that would
establish a high level on the output if it were enabled areVIL = VIL max and VIH = VIH min. Each output istested individually.

4.6.24IOZPD Power-Down Off-State (High-Impedance State) Output Current (of a 3-State Output)
JEDEC - no definition offered
TI - The current flowing into an output that is switched to or held in the high-impedance state as the device
is being powered down to VCC = 0 V.
TI data sheets specify currents flowing out of a device as a negative value.
Power-up 3-state (PU3S) circuitry is characterized by the parameters IOZPD and IOZPU. For hot-insertion
support, Ioff, and the addition of IOZPD and IOZPU are necessary. The TI logic families with the Ioff and PU3S
features that support hot insertion are: ABT (some), ALVT, BCT, LVT, and LVCZ.
While Ioff is tested in a steady-state dc environment, PU3S is checked dynamically by ramping the power
supply from 0 V to its maximum recommended value, then back to 0 V. The power-up and power-down
ramp rates also affect the internal circuitry, but a ramp rate faster than 20 µs/V is not recommended for
GTLP devices, for example, and slower than that (~200 µs/V) for older logic technologies. This ramp rate
sometimes is specified as Δt/ΔVCC in the Recommended Operating Conditions section of the data sheet.
Because typical power supplies power up within a few milliseconds (due, in part, to the enormous
capacitance distributed throughout a PCB), the PU3S circuit should function properly in all applications.
PU3S circuitry disables the logic device outputs at a VCC range of 0 V to a specified power-supply voltage
trip point, regardless of the state of the output enable pin. At a certain guard-banded voltage above this
supply voltage, the device will assert a voltage at the output, as indicated by its respective bit input-voltage
logic level. This is true only if the voltage at the input of the output-enable pin enables the outputs during
normal operation of the device. If the output is required to be in the high-impedance state while the device
is being powered up or powered down throughout the entire range, the output-enable pin must be set todisable the output.
The voltage-versus-time plot shown in Figure 45 demonstrates how PU3S functions. As the device isbeing powered up, until it reaches the minimum VCC supply voltage (labeled Supply Trip Point in
Figure 45), the device output remains in the high-impedance state and remains at the pullup voltage, as
defined by the load at the output. Once the internal PU3S circuitry determines that the supply voltage isslightly above this trip point, the device resumes normal functionality and enables the output. In this case,the input pin is such that the output goes low when enabled. The falling edge of the power-supply voltage
shows similar results: just before VCC reaches this trip point, the output is disabled.
For further information on power-up 3-state, refer to the TI application report, Power-Up 3-State (PU3S)
Circuits in TI Standard Logic Devices, literature number SZZA033.

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Power Supply

V CC

PullupVoltageHigh Output
Impedance

Test forI OZPU

Test forI OZPDHigh Output
Impedance

ActiveRegionSupply Trip
Point

Logic Output
V OL
0V
Time

Figure 45. TI Logic Device I/O Text for IOZPU and IOZPD
4.6.25IOZPU Power-Up Off-State (High-Impedance State) Output Current (of a 3-State Output)
JEDEC - no definition offered
TI - The current flowing into an output that is switched to or held in the high-impedance state as the device
is being powered up from VCC = 0 V.
See IOZPD power-down off-state output current for further information.
TI data sheets specify currents flowing out of a device as a negative value.

4.6.26ICEX Output High Leakage Current
JEDEC - no definition offered
TI - The maximum leakage current into an output that is in the high state and VO = VCC.

4.6.27ICC Supply Current
JEDEC - ICCH is the current into a supply terminal of an integrated circuit when the output is (all outputsare) at a high-level voltage. ICCL is the current into a supply terminal of an integrated circuit when the
output is (all outputs are) at a low-level voltage.
TI - The current into the VCC supply terminal of an integrated circuit.
This parameter is the current into the VCC supply terminal of an integrated circuit under static no-loadconditions. ICC is tested by applying the specified VCC level and measuring the current into the device.
The outputs of the device are left open, while all inputs—control and data—are biased to either VCC or
GND. For CMOS technologies, this is done to eliminate any current that may be caused by any input
conditions or output loads.

4.6.28ΔICC Supply-Current Change
JEDEC - no definition offered
TI - The increase in supply current for each input that is at one of the specified TTL voltage levels, rather
than 0 V or VCC.

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If n inputs are at voltages other than 0 V or VCC, the increase in supply current will be n × ICC. The change
in supply current (ICC) is tested by applying the specified VCC level, setting one input lower than VCC (forexample, VCC - 0.6 V for LVC and ALVC devices) and all other inputs the same as the ICC test, at 0 V or
VCC, then measuring the current into the device (see Figure 46). The outputs of the device are open, as
well. The ΔICC specification typically is useful only on CMOS products that are designed to be operated at
5 V or 3.3 V because its purpose is to provide information about the supply-current performance of the
CMOS device when driven by 5-V TTL signal levels.

VCC = 5 VAC
5ICC − mA

4
3
2
1

AHC

0

1

2

3

4

5

Input Voltage − V

Figure 46. Example Typical AC and AHC ICC vs Input Voltage
Helpful Hint:
Use the ΔICC specification as a reference when driving a CMOS device input with a TTL output driver.
Helpful Hint:
The ΔICC specification also demonstrates the high currents that can occur if VIH and VIL recommended
operating conditions are not observed.
4.6.29Ci Input Capacitance
JEDEC - no definition offered
TI - The capacitance of an input terminal of the device.
This parameter is the internal capacitance encountered at an input of the device. The values that are
given are not production-tested values. Normally, they are typical values given for the benefit of thedesigner. These values are established by the design, process, and package of the device.

4.6.30Cio Input/Output Capacitance
JEDEC - no definition offered
TI - The capacitance of an input/output (I/O) terminal of the device with the input conditions applied that,
according to the product specification, establishes the high-impedance state at the output.
This parameter is the internal capacitance encountered at an input/output (I/O) of the device. The values
that are given are not production-tested values. Normally, they are typical values given for the benefit ofthe designer. These values are established by the design, process, and package of the device.

4.6.31Co Output Capacitance
JEDEC - no definition offered

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TI - The capacitance of an output terminal of the device with the input conditions applied that, according to
the product specification, establishes the high-impedance state at the output.
This parameter is the internal capacitance encountered at an output of the device. The values that are
given are not production-tested values. Normally, they are typical values given for the benefit of thedesigner. These values are defined by the design, process, and package of the device.

4.7

Live-Insertion Specifications
In addition to the following parameters, Ioff, IOZPU, and IOZPD are specified in the live-insertion table because
these parameters are necessary for live-insertion applications and typically are not stated in the electricalcharacteristics section of the data sheet, if already mentioned in this section.

4.7.1

ICC (BIAS VCC) BIAS VCC Current
JEDEC - no definition offered
TI - This specification defines the maximum current at the BIAS VCC pin during the ramp up or ramp downof the VCC voltage.

4.7.2

VO Output Bias Voltage
JEDEC - no definition offered
TI - This specification defines the range of voltages that will be applied to the output pin when the device
is powered down.

4.7.3

IO Output Bias Current
JEDEC - no definition offered
TI - This specification defines the minimum current measured at the output pin when the device ispowered down.

4.8

Timing Requirements

4.8.1

fclock Clock Frequency
JEDEC - no definition offered
TI - This specification defines the range of clock frequencies over which a bistable device can be operated
while maintaining stable transitions between logic levels at the outputs.
The fclock parameter is tested by driving the clock input with a predetermined number of pulses. The output
then is checked for the correct number of output transitions corresponding to the number of input pulses
applied. The output is loaded as defined in the data sheet specifications. Each output is individually tested
and not checked simultaneously with other recommended operating conditions or propagation delays. For
counters, shift registers, or any other devices for which the state of the final output is dependent on thecorrect operation of the previous outputs, fclock will be tested only on the final output, unless specified
independently in the data sheet. Full functionality testing is not performed during fclock testing or fmax testing.
Helpful Hint:
The fmax and fclock parameters are two sides of the same coin. The fclock parameter tells you, the user, howfast you can reliably switch the input to the device. The fmax parameter informs TI when to reject a device
that fails to function below a minimum speed. If you are a device user, you should simply disregard the fmax
specification and use the fclock specification.
Helpful Hint:
For products that are not clocked (for example, buffers and transceivers) for which you would like to know
the maximum operating frequency, an estimate is the fclock value from a comparable clocked part. For
example, an SN74LVC16245A maximum data frequency is conservatively similar to the SN74LVC16374
maximum clock frequency. However, this is highly dependent upon load, and is a rule-of-thumb only.

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4.8.2

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tw Pulse Duration (Width)
JEDEC - The time interval between the specified reference points on the two transitions of the pulse
waveform.
TI - The time interval between specified reference points on the leading and trailing edges of the pulse
waveform.

Input
VoltageA minimum value is specified that is the shortest interval for which correct operation of the digital circuit isspecified (see Figure 47). Pulse duration is tested by applying a pulse to the specified input for a time
period equal to the minimum specified in the data sheet. The device passes if the outputs switch to their
expected logic levels and fails if they do not. Pulse-duration times are not checked simultaneously withother inputs or other recommended operating conditions.

tw

VIH

Data
Input

VT

VT

VIL

Time

Figure 47. Pulse Duration

4.8.3

tsu Setup TimeJEDEC - The time interval between the application of a signal at a specified input terminal and asubsequent active transition at another specified input terminal.
TI - The time interval between the application of a signal that is maintained at a specified input terminal
and a consecutive active transition at another specified input terminal.
NOTE: 1. The setup time is the time interval between two signal events and is determined by thesystem in which the digital circuit operates. A minimum value is specified that is the shortest
interval for which correct operation of the digital circuit is specified.

NOTE: 2. The setup time may have a negative value, in which case the minimum limit defines thelongest interval (between the active transition and the application of the other signal) for
which correct operation of the digital circuit is specified.

Setup time is tested by switching an input to a fixed logic level at a specified time before the transition of
the other input (see Figure 48). The device passes if the outputs switch to their expected logic levels andfails if they do not. Setup times are not checked simultaneously with other inputs or other recommended
operating conditions. For additional information about setup time, refer to the TI application report,
Metastable Response in 5-V Logic Circuits, literature number SDYA006.

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4.8.4

th Hold TimeJEDEC - The time interval during which a signal is retained at a specified input terminal after an active
transition occurs at another specified input terminal.
TI - The time interval during which a signal is retained at a specified input after an active transition occurs
at another specified input.
NOTE: 1. The hold time is the actual time interval between two signal events and is determined by
the system in which the digital signal operates. A minimum value is specified that is theshortest interval for which correct operation of the digital circuit is to be expected.

NOTE: 2. The hold time may have a negative value, in which case, the minimum limit defines thelongest interval (between the release of the signal and the active transition) for which correct
operation of the digital circuit is to be expected.

Hold time is tested by holding an input at a fixed logic level for the specified time after the transition of theother input (see Figure 48). The device passes if the outputs switch to their expected logic levels and fails
if they do not. Hold times are not checked simultaneously with other inputs or other recommended
operating conditions. For additional information about hold time, refer to the TI application report;
Metastable Response in 5-V Logic Circuits, literature number SDYA006.

Input Voltage

VIH

Timing
Input

VT

VIL

Time
tsu

th

Input Voltage

VIH

Data
Input

VT

VT

VIL

Time

Figure 48. Setup and Hold Times

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4.9
4.9.1

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Switching Characteristics
fmax Maximum Clock Frequency
JEDEC - The highest frequency at which a clock input of an integrated circuit can be driven, while
maintaining proper operation.
TI - The highest rate at which the clock input of a bistable circuit can be driven through its requiredsequence, while maintaining stable transitions of logic level at the output with input conditions establishedthat should cause changes of output logic level in accordance with the specification.
The fmax value is the value of the upper limit of the fclock specification, and is specified in the data sheet as aminimum limit. The circuit is specified to operate up to the minimum frequency value. See fclock for
additional fmax testing information. Due to test-machine capability limitations, it may be necessary to test
fmax or minimum recommended operating conditions (that is, pulse duration, setup time, hold time) in
accordance with the following paragraph.
The fmax parameter may be tested in either of two ways. One method is to test simultaneously the
responses to the symmetrical clock-high and clock-low pulse durations that correspond to the period of thespecified minimum value of fmax. The second method is to test individually the responses to the minimum
clock-high and clock-low pulse durations under specified load conditions. A pulse generator is used topropagate a signal through the device to verify device operation with the minimum pulse duration. Whenclock-high and clock-low pulse durations are equal to or less than the corresponding fmax pulse duration,
fmax testing suffices for testing clock-high and clock-low pulse durations.
Helpful Hint:
The fmax and fclock parameters are two sides of the same coin. The fclock parameter tells you, the user, howfast you can reliably switch the input to the device. The fmax parameter informs TI when to reject a device
that fails to function below a minimum speed. If you are a device user, you should simply disregard the fmax
specification and use the fclock specification.
Helpful Hint:
For products that are not clocked (for example, buffers and transceivers) for which you would like to know
the maximum operating frequency, an estimate is the fclock value from a comparable clocked part. For
example, an SN74LVC162451A maximum data frequency is conservatively similar to the SN74LVC16374
maximum clock frequency. However, this is highly dependent upon load and is a rule-of-thumb only.

4.9.2

tpd Propagation Delay TimeJEDEC - The time interval between specified reference points on the input and output voltage waveforms
with the output changing from one defined level (high or low) to the other defined level.
TI - The time between the specified reference points on the input and output voltage waveforms, with theoutput changing from one defined level (high or low) to the other defined level (tpd = tPHL or tPLH).
A common misconception about logic devices is that the maximum data-signaling rate (or maximum
frequency, as it is commonly misnamed) is equal to the inverse of the propagation delay. The maximum
data rate on buffers is dependent on several factors, such as propagation delay matching, input sensitivity,and output edge rates. A device can have a high maximum signaling rate if the propagation delays from
low-to-high and high-to-low are matched, the input is fast enough to respond to the fast data rate, and theoutput edge rate does not interfere with the low and high-level steady states. Clocked devices behave inthe same manner, but now the set-up and hold times must be taken into account.
Helpful Hint:
The maximum value of tPD simply is the worst case of tPHL or tPLH.
Helpful Hint:
Bus switch devices such as CBT and CBTLV typically are specified with a maximum limit of 0.25 ns. This
limit is not a measured value, but is derived from the calculated RC time constant of the typical on-state
resistance of the switch and the specified load capacitance, when driven by an ideal voltage source (zerooutput impedance).

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4.9.3

tPHL Propagation Delay Time, High-Level to Low-Level Output
JEDEC - The time interval between specified reference points on the input and output voltage waveforms
with the output changing from the defined high level to the defined low level.
TI - The time between the specified reference points on the input and output voltage waveforms, with theoutput changing from the defined high level to the defined low level.
Propagation delay time, tPHL, is tested by causing a transition on the specified input that causes thedesignated output to switch from a high logic level to a low logic level. For example, the transition applied
is 0 V to VCC or VCC to 0 V for AC devices and 0 V to 3 V or 3 V to 0 for ACT devices. Trip points used forthe timing measurements and output loads used during testing are defined in the individual data sheets in
the Parameter Measurement Information section, typically found after the Switching Characteristics (overrecommended ranges of supply and operating free-air temperature) table. Propagation delay time, tPHL, is
not checked simultaneously with other outputs or with other recommended operating conditions. The time
between the specified reference point on the input voltage waveform and the specified reference point on
the output voltage waveform is measured.

4.9.4

tPLH Propagation Delay Time, Low-Level to High-Level Output
JEDEC - The time interval between specified reference points on the input and output voltage waveforms
with the specified output changing from the defined low level to the defined high level.
TI - The time between the specified reference points on the input and output voltage waveforms, with theoutput changing from the defined low level to the defined high level.
Propagation delay time, tPLH, is tested by causing a transition on the specified input that causes thedesignated output to switch from a low logic level to a high logic level. For example, the transition applied
is 0 V to VCC or VCC to 0 V for AC devices and 0 V to 3 V or 3 V to 0 for ACT devices. Trip points used forthe timing measurements and output loads used during testing are defined in the individual data sheets in
the Parameter Measurement Information section, typically found after the Switching Characteristics (overrecommended ranges of supply and operating free-air temperature) table. Propagation delay time, tPLH, isnot checked simultaneously with other outputs or with other recommended operating conditions. The time
between the specified reference point on the input voltage waveform and the specified reference point on
the output voltage waveform is measured.

4.9.5

ten Enable Time (of a 3-State or Open-Collector Output)
JEDEC - The propagation time between specified reference points on the input and output voltage
waveforms with the output changing from a high-impedance (off) state to either of the defined active levels(high or low).
TI - The propagation time between the specified reference points on the input and output voltage
waveforms, with the output changing from the high-impedance (off) state to either of the defined active
levels (high or low).
NOTE: Open-collector outputs change only if they are responding to data that would cause theoutput to go low, so ten = tPHL.

4.9.6

tPZH Enable Time (of a 3-State Output) to High Level
JEDEC - The propagation time between specified reference points on the input and output voltage
waveforms with the output changing from a high-impedance (off) state to the defined high level.
TI - The time interval between the specified reference points on the input and output voltage waveforms,
with the 3-state output changing from the high-impedance (off) state to the defined high level.
This parameter is the propagation delay time between the specified reference point on the input voltage
waveform and the specified reference point on the output voltage waveform, with the 3-state output
changing from the high-impedance (off) state to the defined high level. Output enable time, tPZH, is tested
by generating a transition on the specified input that will cause the designated output to switch from thehigh-impedance state to a high logic level. Trip points used for the timing measurements and output loads
used during testing are defined in the individual data sheets in the Parameter Measurement Information

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section, typically found after the Switching Characteristics (over recommended ranges of supply andoperating free-air temperature) table. Output enable time, tPZH, is not checked simultaneously with other
outputs or with other recommended operating conditions. Outputs not being tested should be set to acondition that minimizes switching currents. The tested output load includes a pulldown resistor to obtain avalid logic-low level when the output is in the high-impedance state.
4.9.7

tPZL Enable Time (of a 3-State Output) to Low Level
JEDEC - The propagation time between specified reference points on the input and output voltage
waveforms with the output changing from a high-impedance (off) state to the defined low level.
TI - The time interval between the specified reference points on the input and output voltage waveforms,
with the 3-state output changing from the high-impedance (off) state to the defined low level.
This parameter is the propagation delay time between the specified reference point on the input voltage
waveform and the specified reference point on the output voltage waveform, with the 3-state output
changing from the high-impedance (off) state to the defined low level. Output enable time, tPZL, is tested bygenerating a transition on the specified input that will cause the designated output to switch from the highimpedance state to a low logic level. Trip points used for the timing measurements and output loads usedduring testing are defined in the individual data sheets in the Parameter Measurement Information section,
typically found after the Switching Characteristics (over recommended ranges of supply and operating
free-air temperature) table. Output enable time, tPZL, is not checked simultaneously with other outputs orwith other recommended operating conditions. Outputs not being tested should be set to a condition thatminimizes switching currents. The tested output load includes a pullup resistor to obtain a valid logic-highlevel when the output is in the high-impedance state.

4.9.8

tdis Disable Time (of a 3-State or Open-Collector Output)
JEDEC - no definition offered
TI - The propagation time between the specified reference points on the input and output voltage
waveforms, with the output changing from either of the defined active levels (high or low) to the highimpedance (off) state.
NOTE: For 3-state outputs, tdis = tPHZ or tPLZ. Open-collector outputs change only if they are low at thetime of disabling, so tdis = tPLH.

4.9.9

tPHZ Disable Time (of a 3-State Output) From High Level
JEDEC - The propagation time between specified reference points on the input and output voltage
waveforms with the output changing from the defined high level to a high-impedance (off) state.
TI - The time interval between the specified reference points on the input and the output voltage
waveforms, with the 3-state output changing from the defined high level to the high-impedance (off) state.

4.9.10tPLZ Disable Time (of a 3-State Output) From Low Level
JEDEC - The propagation time between specified reference points on the input and output voltage
waveforms with the output changing from the defined low level to a high-impedance (off) state.
TI - The time interval between the specified reference points on the input and the output voltage
waveforms, with the 3-state output changing from the defined low level to the high-impedance (off) state.

4.9.11

tf Fall TimeJEDEC - The time interval between one reference point on a waveform and a second reference point ofsmaller magnitude on the same waveform.
TI - The time interval between two reference points (90% and 10%, unless otherwise specified) on a
waveform that is changing from the defined high level to the defined low level.

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4.9.12tr Rise TimeJEDEC - The time interval between one reference point on a waveform and a second reference point ofgreater magnitude on the same waveform.
TI - The time interval between two reference points (10% and 90%, unless otherwise specified) on a
waveform that is changing from the defined low level to the defined high level.

4.9.13Slew RateJEDEC - no definition offered
TI - The voltage rate of change of an output (ΔV/Δt).

4.9.14tsk(i) Input Skew
JEDEC - The magnitude of the difference in propagation delay times between two inputs and a single
output of an integrated circuit at identical operating conditions.
TI - The difference between any two propagation delay times that originate at different inputs andterminate at a single output. Input skew describes the ability of a device to manipulate (stretch, shrink, orchop) a clock signal. Typically, this is accomplished with a multiple-input gate wherein one of the inputs
acts as a controlling signal to pass the clock through. tsk(i) describes the ability of the gate to shape thepulse to the same duration, regardless of the input used as the controlling input.

4.9.15tsk(l) Limit Skew
JEDEC - The difference between (1) the greater of the maximum specified values of propagation delay
times tPLH and tPHL, and (2) the lesser of the minimum specified values of propagation delay times tPLH andtPHL.
TI - The difference between: the greater of the maximum specified values of tPLH and tPHL and the lesser ofthe minimum specified values of tPLH and tPHL. Limit skew is not directly observed on a device and is
calculated from the data sheet limits for tPLH and tPHL. tsk(l) quantifies for the designer how much variation inpropagation delay time is induced by operation over the entire ranges of supply voltage, temperature,
output load, and other specified operating conditions. Specified as such, tsk(l) also accounts for process
variation. In fact, all other skew specifications (tsk(o), tsk(i), tsk(p), and tsk(pr)) are subsets of tsk(l); they never are
greater than tsk(l).

4.9.16tsk(o) Output Skew
JEDEC - The skew time between two outputs of a single integrated circuit with all driving inputs switching
simultaneously and the outputs switching in the same direction while driving identical loads.
TI - The skew between specified outputs of a single logic device, with all driving inputs connected together
and the outputs switching in the same direction while driving identical specified loads.

4.9.17tsk(p) Pulse Skew
JEDEC - The magnitude of the difference between the propagation delay times tPHL and tPLH when a single
switching input causes one or more outputs to switch.
TI - The magnitude of the time difference between the propagation delay times, tPHL and tPLH, when asingle switching input causes one or more outputs to switch.

4.9.18tsk(pr) Process Skew
JEDEC - The part-to-part skew time between corresponding terminals of two samples of an integrated
circuit from a single manufacturer.
TI -The magnitude of the difference in propagation delay times between corresponding terminals of two
logic devices when both logic devices operate with the same supply voltages, operate at the same
temperature, have identical package styles, have identical specified loads, have identical internal logic
functions, and have the same manufacturer.

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Helpful Hint:
Process variation is the only factor that affects process skew.

4.10 Noise Characteristics
4.10.1

VOL(P) Quiet Output, Maximum Dynamic VOL
JEDEC - no definition offered
TI - The maximum positive voltage level at an output terminal with input conditions applied that, according
to the product specification, establishes a low level at the specified output and a high-to-low transition at
all other outputs.
Commonly called ringback, this parameter is the peak voltage of an output in the quiescent low condition,
while all other outputs are switched from high to low (see Figure 49). Sometimes called a one-quiet-low
test, this is a simultaneous switching measurement and indicates a device's noise performance due topower-rail and ground-rail bounce caused by the high peak currents during dynamic switching. VOL(P) also
can apply to a switching output just after a high-to-low transition.

VOH(P)(Quiet High)

Output Voltage

VOH
VOH(V)

VOL(P)(Quiet Low)
VOL
VOL(V)
Time

Figure 49. Output Noise Characteristics

4.10.2VOL(V) Quiet Output, Minimum Dynamic VOL
JEDEC - no definition offered
TI - The maximum negative voltage level at an output terminal with input conditions applied that, according
to the product specification, establishes a low level at the specified output and a high-to-low transition at
all other outputs.
Commonly called undershoot, this parameter is the valley voltage of an output in the quiescent low
condition, while all other outputs are switched from high to low (see Figure 49). Sometimes called a onequiet-low test, this is a simultaneous-switching measurement and indicates a device's noise performancedue to power-rail and ground-rail bounce caused by the high peak currents during dynamic switching.
VOL(V) also can apply to a switching output during a high-to-low transition.

4.10.3

VOH(P) Quiet Output, Maximum Dynamic VOH
JEDEC - no definition offered

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TI - The maximum positive voltage level at an output terminal with input conditions applied that, according
to the product specification, establish a high level at the specified output and a low-to-high transition at allother outputs.
Commonly called overshoot, this parameter is the peak voltage of an output in the quiescent highcondition, while all other outputs are switched from low to high (see Figure 49). Sometimes called a onequiet-high test, this is a simultaneous-switching measurement and indicates a device's noise performancedue to power-rail and ground-rail bounce caused by the high peak currents during dynamic switching.
VOH(P) also can apply to a switching output during a low-to-high transition.
4.10.4

VOH(V) Quiet Output, Minimum Dynamic VOH
JEDEC - no definition offered
TI - The minimum positive voltage level at an output terminal with input conditions applied that, according
to the product specification, establishes a high level at the specified output and a low-to-high transition at
all other outputs.
Commonly called ringback, this parameter is the valley voltage of an output in the quiescent highcondition, while all other outputs are switched from low to high (see Figure 49). Sometimes called a onequiet-high test, this is a simultaneous-switching measurement and indicates a device's noise performancedue to power-rail and ground-rail bounce caused by the high peak currents during dynamic switching.
VOH(V) also can apply to a switching output just after a low-to-high transition.

4.10.5

VIH(D) High-Level Dynamic Input Voltage
JEDEC - no definition offered
TI - An input voltage during dynamic switching conditions within the more positive (less negative) of thetwo ranges of values used to represent the binary variables.
NOTE: A minimum is specified that is the least positive value of high-level input voltage for which
operation of the logic element within specification limits is to be expected.

High-level dynamic input voltage is a measurement of the shift of the input threshold due to noise
generated while under the multiple-outputs-switching condition, with outputs operating in phase. This test
is package and test-environment sensitive.
4.10.6

VIL(D) Low-Level Dynamic Input Voltage
JEDEC - no definition offered
TI - An input voltage during dynamic switching conditions within the less positive (more negative) of thetwo ranges of values used to represent the binary variables.
NOTE: A maximum is specified that is the most positive value of low-level input voltage for which
operation of the logic element within specification limits is to be expected.

Low-level dynamic input voltage is a measurement of the shift of the input threshold due to noise
generated while under the multiple-outputs-switching condition, with outputs operating in phase. This test
is package and test-environment sensitive.

4.11 Operating Characteristics
4.11.1

Cpd Power-Dissipation Capacitance
JEDEC - no definition offered
TI - This parameter is the equivalent capacitance used to determine the no-load dynamic power
dissipation per logic function for CMOS devices. PD = Cpd VCC 2 f + ICC VCCSZZA036C – December 2002 – Revised June 2016
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The Cpd test is a measure of the dynamic power a device requires with a specific load. The values givenon the data sheet are typical values that are not production tested. These values are defined by thedesign and process of the device. For more information on Cpd, refer to the TI application report, CMOS
Power Consumption and Cpd Calculation, literature number SCAA035.

4.12 Parameter Measurement Information
The Parameter Measurement Information (PMI) section of a data sheet is a graphical illustration of the test
conditions used to characterize a logic device. Usually this includes a load schematic, example waveforms
with measurement points, and related notes. The PMI that is attached to each data sheet is typically ageneric PMI for the entire logic family and may include additional information that is not used for thatspecific device. For example, the voltage waveforms for enable and disable times (which are used on
devices with 3-state outputs) may be included in the data sheet of a device without 3-state outputs. This issuperfluous information for the specific device and can be disregarded. The PMI may include the test
information for multiple VCCs in one page, with a table of test-load circuit and measurement point
information, or the test information for each separate VCC range at which the device operates may be inseparate PMI pages, in which case the VCC range will be stated at the top of the PMI illustration. Relevantload and test setup information also is included in the footnotes at the bottom of the PMI illustration.

5

Logic Compatibility
Logic compatibility has become more prevalent since the first 3.3-V logic devices were introduced into themarket, creating an evolutionary trend in logic ICs. The trend demands that lower power-supply-voltage
devices have the capability to communicate with older 5-V devices. In time, power-supply nodes havedecreased even further, mainly due to power-consumption reduction. This reduction in supply nodes,
coupled with the fact that 5-V systems are not only still in use, but thriving, has forced logic manufacturers
to provide logic devices that are compatible with technologies from several different output-voltage levels(see Table 3).
Table 3. Key Parameters per Technology for Logic Compatibility
TECHNOLOGYPORT(S)

VCC MIN(V)

I/O VOLTAGE
TOLERANCE(V)

VIH MIN(V)

VIL MAX(V)

VOH MIN
AT GIVEN
CURRENT(V)

VOL MAXAT GIVEN
CURRENT(V)

ABT

A and B

4.5

5

2

0.8

2.5 (at -3 mA)

Not specified

AHC

A and B

2 (at -32 mA)

Not specified

Not specified

0.55 (at 64 mA)

2

VCC + 0.5

1.5

0.5

3

VCC + 0.5

2.1

0.9

2.48 (at -4 mA)

0.44 (at 4 mA)

4.5

VCC + 0.5

Not Specified

3.8 (at -8 mA)

0.44 (at 8 mA)

5.5

VCC + 0.5

3.85

1.65

Not specified

Not specified

NOTE: These values are general technology performance characteristics. Because these values arederived from standard '245 or '16245 functions, carefully read the data sheet for each device
for exact performance values.

Suppose you have created Table 3, which details the most important parameters discussed in theprevious section that affect the compatibility of one device to another. Using the table to determine if aport from one technology is compatible to another, simply compare the VOH min and VOL max levels to the
input threshold (VIH min and VIL max). If the output dc steady-state logic-high and logic-low voltage levels(VOH and VOL) are outside of the minimum VIH and maximum VOL range of an input port, then, in general,
one can consider these two ports compatible (see Figure 50).

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Detailed Description

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INTERFACE

Output

VCC

High

VCC

High Noise Margin

Input

VOH (min)High
VIH (min)

VIL (max)

Low
Low

VOL (max)
GND

GND

Low Noise Margin

Copyright © 2016, Texas Instruments Incorporated

Figure 50. Logic Compatibility Between I/Os
For example, is the A-port output of an ABT device compatible with a B-port input of the same
technology? Because the input of an ABT device is CMOS technology (II input current was discussed for
determination of CMOS or bipolar input type), if it is connected in a point-to-point topology with an ABT
output, the static dc current will be very low-leakage current range-and the VOH level will not be lower than
2.5 V and the VOL level will be no greater than 0.55 V. The input threshold to any ABT input port is set atthe standard TTL/LVTTL threshold of 0.8 V - 2 V. Because the VOH level of 2.5 V is greater than theminimum VIH level of 2 V, and the VOL level of 0.55 V is less than the maximum VIL level of 0.8 V, thesetwo ports are considered compatible.
Care must be taken when driving bipolar inputs because of the excessive currents at the input. If
sufficiently large, the VOH level could drop (or, conversely, the VOL level could increase) to a level that
violates the input threshold of the receiver.
Another major consideration is the voltage tolerance of the I/O structure. Simply because the previous
conditions were satisfied, that does not mean I/Os are compatible. Take, for example, the same ABT
output, which, if driving a CMOS input, will provide a VOH level that will not be lower than 2.5 V and a VOL
level that will be no greater than 0.55 V, to drive an AHC input (which is CMOS) powered with a 3-V
supply. The input threshold is met (that is, 2.5 V > 2.1 V and 0.55 V < 0.9 V), but the I/O voltage tolerance
is only 3.5 V (3 V + 0.5 V). An ABT output is very capable of producing voltage logic-high levels greaterthan 3.5 V, therefore, an ABT (5-V VCC) output is not compatible to an AHC input powered with a 3-V
supply.

6

Detailed Description
The detailed description of the device including the functional block diagram of the device, functionalmodes which defines the truth table, feature description explaining in detail about the unique features ofthe device described in the initial page of the data sheet, belongs in this section.

7

Application and Implementation
This section details the device's typical application which it could be used for. The design requirements
goes into detailing the design criteria and the calculation involved. Usually the recommended operating
conditions and the absolute maximum conditions are highlighted to reinforce the device's capabilities andrestrictions. The typical characteristics curve helps to describe the application's expected output.

SZZA036C – December 2002 – Revised June 2016
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57

Power Supply Recommendations

www.ti.com

AND Logic Function

Basic LED Driver

VCC

VCC

A- uC or Logic

A- uC or Logic
Y- uC or Logic

B- uC or Logic

LVC1G08

B- uC or Logic

LVC1G08

Figure 51. Typical Application for SN74LVC1G08

8Power Supply Recommendations
Power supply guidelines are the best practice while using the device in the application described in thissection. The operating voltage range of the device apart from the bypass caps which are best suited are
discussed.

9

LayoutGeneral layout guidelines for optimum performance of the device is discussed in this section. Basic rulesof biasing the floating inputs which, otherwise, could cause instability in the application are among the
topics discussed in this section.

10

Conclusion
The information in this application report is provided so that the designer can derive the maximum amountof information about standard-logic devices from the device data sheets. Texas Instruments provides thisinformation to ease the task of the designer in incorporating standard-logic products into new systemdesigns and upgrading legacy systems.

11

Acknowledgments
The authors thank Michael Cooper, Craig Spurlin, Mac McCaughey, and Sandi Denham for reviewing the
document and providing meaningful feedback.

12

References
1. JESD88 - JEDEC Dictionary of Terms for Solid State Technology, First Edition, JEDEC Solid State
Technology Association, Arlington, VA, September 2001.
2. Semiconductor Group Packaging-Outlines Reference Guide, SSYU001, Texas Instruments.
3. JEP103A - Suggested Product-Documentation Classifications and Disclaimers, Electronic Industries
Association, Arlington, VA, July 1996.
4. CMOS Power Consumption and Cpd Calculation, SCAA035, Texas Instruments.
5. Bus-Hold Circuit, SCLA015, Texas Instruments.
6. JESD51-3 - Low Effective Thermal Conductivity Test Board For Leaded Surface Mount Packages,
JEDEC Solid State Technology Association, Arlington, VA, August 1996.
7. Thermal Characteristics of Standard Linear and Logic (SLL) Packages and Devices, SCZA005, Texas
Instruments.
8. Logic in Live-Insertion Applications With a Focus on GTLP, SCEA026, Texas Instruments.

58

Understanding and Interpreting Standard-Logic Data Sheets

SZZA036C – December 2002 – Revised June 2016
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References

www.ti.com

9. Dynamic Output Control (DOC™) Circuitry Technology and Applications, SCEA009, Texas
Instruments.
10. Implications of Slow or Floating CMOS Inputs, SCBA004, Texas Instruments.
11. JESD51-7 - High Effective Thermal Conductivity Test Board For Leaded Surface Mount Packages,
JEDEC Solid State Technology Association, Arlington, VA, February 1999.
12. Power-Up 3-State (PU3S) Circuits in TI Standard Logic Devices, SZZA033

SZZA036C – December 2002 – Revised June 2016
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