Sample &Buy

Product
FolderSupport &Community

Tools &
SoftwareTechnical
Documents

TPS62740, TPS62742
SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

TPS6274x 360nA IQ Step Down Converter For Low Power Applications
1 Features

3 Description

•
•
•
•

The TPS6274x is industry's first step down converterfeaturing typ. 360nA quiescent current and operatingwith a tiny 2.2µH inductor and 10µF output capacitor.
This new DCS-Control™ based device extends thelight load efficiency range below 10µA load currents.
TPS62740 supports output currents up to 300mA,
TPS62742 up to 400mA. The device operates fromrechargeable Li-Ion batteries, Li-primary battery
chemistries such as Li-SOCl2, Li-MnO2 and two or
three cell alkaline batteries. The input voltage range
up to 5.5V allows also operation from a USB port andthin-film solar modules. The output voltage is user
selectable by four VSEL pins within a range from
1.8V to 3.3V in 100mV steps. TPS6274x features low
output ripple voltage and low noise with a small
output capacitor. Once the battery voltage comesclose to the output voltage (close to 100% duty cycle)
the device enters no ripple 100% mode operation toprevent an increase of output ripple voltage. The
device then stops switching and the output isconnected to the input voltage. The integrated slew
rate controlled load switch provides typ. 0.6Ω onresistance and can distribute the selected output
voltage to a temporarily used sub-system. The
TPS6274x is available in a small 12 pin 2 × 3mm2
WSON package and supports a total solutions size of
31mm2.

1

•
•
•
•
•
•
•
•
•
•
•

Input Voltage Range VIN from 2.2V to 5.5
Typ. 360nA Quiescent Current
Up to 90% Efficiency at 10µA Output Current
Up to 300mA / 400mA Output Current(TPS62740/TPS62742)
RF Friendly DCS-Control TM
Up to 2 MHz Switching Frequency
Low Output Ripple Voltage
16 Selectable Output Voltages in 100mV Steps
between 1.8V to 3.3V
Automatic Transition to No Ripple 100% Mode
Slew Rate Controlled Load Switch
Discharge Function on VOUT / LOAD
Power Good Output
Optimized for Operation with a Tiny 2.2µH
Inductor and 10µF COUT
Total Solution Size <31mm2
Small 2 x 3 mm2 WSON Package

2 Applications•••

Bluetooth® Low Energy, RF4CE, Zigbee
Industrial Metering
Energy Harvesting

Device Information(1)PART NUMBER
TPS62740

PACKAGEWSON

TPS62742

BODY SIZE (NOM)
3.00 mm × 2.00 mm(1) For all available packages, see the orderable addendum atthe end of the datasheet.

4 Typical Application
SW
VOUT

2.1V
L 2.2mH Main rail

Rpull up
PG
CTRL
LOAD

100
VCC

COUT
10mF

Switched
supply rail
VCC

Subsystem(Sensors)

95

New
TPS62740

90

Efficiency (%)

CIN
10mF

TPS62740
VIN
EN
VSEL1
VSEL2
VSEL3
VSEL4
GND

Low Power
MCU + RF

VIN
2.2V - 5.5V

85

TPS62740 extends
light load efficiency range
down to 10mA output current

80
75

Current
TM
DCS-Control topology

70
65
60
0.001

VIN = 3.6V
VOUT = 3.3V
0.01

0.1

1

10

100

1000

Output Current (mA)
1

An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.

TPS62740, TPS62742
SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

www.ti.com

Table of Contents
1
2
3
4
5
6
7
8

Features .................................................................. 1
Applications ........................................................... 1
Description ............................................................. 1
Typical Application ................................................ 1
Revision History..................................................... 2
Device Comparison Table..................................... 3
Pin Configuration and Functions ......................... 3
Specifications......................................................... 4
8.1
8.2
8.3
8.4
8.5
8.6

9

Absolute Maximum Ratings ...................................... 4
Handling Ratings ...................................................... 4
Recommended Operating Conditions....................... 5
Thermal Information ................................................. 5
Electrical Characteristics........................................... 5
Typical Characteristics .............................................. 7

Detailed Description .............................................. 8
9.1 Overview ................................................................... 8
9.2 Functional Block Diagram ......................................... 8
9.3 Feature Description................................................... 8

9.4 Device Functional Modes........................................ 1010 Application and Implementation........................ 1210.1 Application Information.......................................... 1210.2 Typical Application ............................................... 1210.3 System Example ................................................... 22

11 Power Supply Recommendations ..................... 23
12 Layout................................................................... 23
12.1 Layout Guidelines ................................................. 23
12.2 Layout Example .................................................... 23

13 Device and Documentation Support ................. 24
13.1
13.2
13.3
13.4
13.5
13.6

Device Support .................................................... 24
Documentation Support ....................................... 24
Related Links ........................................................ 24
Trademarks ........................................................... 24
Electrostatic Discharge Caution ............................ 24
Glossary ................................................................ 24

14 Mechanical, Packaging, and Orderable
Information ........................................................... 24

5 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision A (November 2013) to Revision B

Page

•

Added TPS62742 device ....................................................................................................................................................... 1•

Added efficiency graph, Figure 11........................................................................................................................................ 15

2

Submit Documentation Feedback

Copyright © 2013–2014, Texas Instruments Incorporated

TPS62740, TPS62742
www.ti.com

SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

6 Device Comparison Table
TA

PART NUMBER

OUTPUT VOLTAGE SETTING VSEL 1 - 4

TPS62740–40°C to 85°C

TPS62741(1)

TPS62742(1)

OUTPUT CURRENT[mA]

PACKAGEMARKING

1.8V to 3.3V in 100mV steps

300mA

62740

1.3V to 2.8V in 100mV steps

300mA

-/-

1.8V to 3.3V in 100mV steps

400mA

62742

Device option, contact TI for more details

7 Pin Configuration and Functions
WSON PACKAGE
12-PinDSS PACKAGE(TOP VIEW)
12 EN

EXPOSEDTHERMAL PAD

VIN 1
SW 2
GND 3
CTRL 4
VOUT 5LOAD 611 VSEL1
10 VSEL29 VSEL3
8 VSEL4
7 PG

Pin Functions
PIN

I/O

DESCRIPTION

1PWR

VIN power supply pin. Connect this pin close to the VIN terminal of the input capacitor. A ceramic capacitorof 4.7µF is required.

SW

2

OUT

This is the switch pin and is connected to the internal MOSFET switches. Connect the inductor to thisterminal.

GND

3

PWR

GND supply pin. Connect this pin close to the GND terminal of the input and output capacitor.

CTRL

4

IN

This pin controls the output LOAD pin. With CTRL = low, the output LOAD is disabled. This pin must be
terminated.

VOUT

5

IN

Feedback pin for the internal feedback divider network and regulation loop. An internal load switch isconnected between this pin and the LOAD pin. Connect this pin directly to the output capacitor with a short
trace.

LOAD

6

OUT

This output is controlled by the CTRL Pin. With CTRL high, an internal load switch connects the LOAD pin
to the VOUT pin. The LOAD pin allows to connect / disconnect other system components to the output of
the DC/DC converter. This pin is pulled to GND with CTRL pin = low. The LOAD pin features a soft
switching. If not used, leave the pin open.

PG

7

OUT

Power good open drain output. This pin is high impedance to indicate "Power Good". Connect a external
pull up resistor to generate a "high" level. If not used, this pin can be left open.

VSEL4

8

IN

VSEL3

9

IN

Output voltage selection pins. See Table 1 for VOUT selection. These pins must be terminated and can bechanged during operation.

VSEL2

10

IN

VSEL1

11

IN

EN

12

IN

High level enables the devices, low level turns the device into shutdown mode. This pin must be
terminated.

NC

Not electrically connected to the IC, but must be soldered. Connect this pad to GND and use it as a central
GND plane.

NAME

NO

VIN

EXPOSEDTHERMAL PAD

Copyright © 2013–2014, Texas Instruments Incorporated

Submit Documentation Feedback

3

TPS62740, TPS62742
SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

www.ti.com

Table 1. Output Voltage Setting
DeviceVOUT

VSEL 4

VSEL 3

VSEL 2

VSEL 1

1.8

0

0

0

0

1.9

0

0

0

1

2.0

0

0

1

0

2.1

0

0

1

1

2.2

0

1

0

0

2.3

0

1

0

1

2.4

0

1

1

0

2.5

0

1

1

1

2.6

1

0

0

0

2.7

1

0

0

1

2.8

1

0

1

0

2.9

1

0

1

1

3.0

1

1

0

0

3.1

1

1

0

1

3.2

1

1

1

0

3.3

1

1

1

1

TPS62740 / 42

8 Specifications
8.1 Absolute Maximum Ratings (1)Over operating free-air temperature range (unless otherwise noted)
MIN

Pin voltage (2)

–0.3

6

V

SW (3)–0.3

VIN +0.3V

V

EN, CTRL, VSEL1-4–0.3

VIN +0.3V

V

PG

–0.3

VIN +0.3V

V

–0.3

3.7

V

10

mA

150

°C

IPG

sink current

Maximum operating junction temperature, TJ
(1)
(2)
(3)

UNIT

VIN

VOUT, LOAD
PG pinMAX–40

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.
All voltage values are with respect to network ground terminal GND.
The MAX value VIN +0.3V applies for applicative operation (device switching), DC voltage applied to this pin may not exceed 4V

8.2 Handling Ratings
Tstg

Storage temperature range

V(ESD)(1)(2)

4

Electrostatic discharge

MIN

MAX

UNIT

–65

150

°C

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

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

1000

V

JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process. The human bodymodel is a 100-pF capacitor discharged through a 1.5-kΩ resistor into each pin.
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.

Submit Documentation Feedback

Copyright © 2013–2014, Texas Instruments Incorporated

TPS62740, TPS62742
www.ti.com

SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

8.3 Recommended Operating Conditions
MIN NOM MAX UNIT
Supply voltage VIN (1)VIN
IOUT +I LOAD

2.2

Device output current (sum of IOUT and I LOAD)

5.5

VOUTnom + 0.7V ≤ VIN ≤ 5.5V

TPS62740300

3V ≤ VIN, VOUTnom + 0.7V ≤ VIN ≤ 5.5V

TPS62742

400

VOUTnom ≤ VIN ≤ VOUTnom +0.7V

mA

100

ILOAD

Load current (current from LOAD pin)L

Inductance

COUT

Output capacitance connected to VOUT pin (not including LOAD pin)

22

CLOAD

Capacitance connected to LOAD pin

10

TJ

Operating junction temperature range

-40

125

TA

Ambient temperature range

-40

85

(1)

V

100
1.5

2.2

3.3

µH
µF
°C

The minimum required supply voltage for startup is 2.15V (undervoltage lockout threshold VTH_UVLO+) . The device is functional down to
2V supply voltage (falling undervoltage lockout threshold VTH_UVLO-).

8.4 Thermal Information
THERMAL METRICDSS / 12 PINS

RθJA

Junction-to-ambient thermal resistance

61.8

RθJCtopJunction-to-case (top) thermal resistance

70.9

RθJB

Junction-to-board thermal resistance

25.7

ψJT

Junction-to-top characterization parameter

1.9

ψJB

Junction-to-board characterization parameter

25.7

RθJCbot

Junction-to-case (bottom) thermal resistance

7.2

UNIT

°C/W

8.5 Electrical Characteristics
VIN = 3.6V, TA = –40°C to 85°C typical values are at TA = 25°C (unless otherwise noted)
PARAMETERTEST CONDITIONS

MIN

TYP

MAX

UNIT

5.5

V

SUPPLY
VIN

Input voltage
range

IQ

Operatingquiescent current

ISD

Shutdown current

VTH_UVLO+
VTH_UVLO-

Undervoltage
lockout threshold

2.2
EN = VIN, CTRL = GND, IOUT = 0µA, VOUT = 1.8V, device not switching,360

EN = VIN, IOUT = 0mA, CTRL = GND, VOUT = 1.8V , device switching460

EN = VIN, IOUT = 0mA., CTRL = VIN, VOUT = 1.8V, device not switching

12.5

1800

nA
µA

EN = GND, shutdown current into VIN

70

1000

EN = GND, shutdown current into VIN, TA = 60°C

150

450

Rising VIN

2.075

2.15

Falling VIN

1.925

2

nA

V

INPUTS EN, CTRL, VSEL 1-4
VIH THHigh level input
threshold

2.2V ≤ VIN ≤ 5.5V

VIL TH

Low level input
threshold

2.2V ≤ VIN ≤ 5.5V

IIN

Input bias Current

TA = 25°C

10

TA = –40°C to 85°C

25

1.1
0.4

V
V
nA

POWER SWITCHESRDS(ON)High side
MOSFET onresistanceLow Side
MOSFET onresistance

0.6

0.85
Ω

VIN = 3.6V, IOUT = 50mA

Copyright © 2013–2014, Texas Instruments Incorporated

0.36

0.5

Submit Documentation Feedback

5

TPS62740, TPS62742
SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

www.ti.com

Electrical Characteristics (continued)
VIN = 3.6V, TA = –40°C to 85°C typical values are at TA = 25°C (unless otherwise noted)
PARAMETER

ILIMF

MIN

TYP

MAX

High side
MOSFET switch
current limit

2.2V ≤ VIN ≤ 5.5V, TPS62740

TEST CONDITIONS

480

600

720

3.0V ≤ VIN ≤ 5.5V, TPS62742

590

650

740

Low side MOSFET
switch current limit

TPS62740

600

TPS62742

650

UNIT
mA

mA

OUTPUT DISCHARGE SWITCH (VOUT)RDSCH_VOUT

MOSFET onresistance

VIN = 3.6V, EN = GND, IOUT = -10mA into VOUT pin

30

IIN_VOUT

Bias current into
VOUT pin

VIN = 3.6V, EN = VIN, VOUT = 2V, CTRL =
GND

RLOAD

High side
MOSFET onresistance

ILOAD = 50mA, CTRL = VIN, VOUT = 2.0V, 2.2 V ≤ VIN ≤ 5.5V

RDSCH_LOAD

Low side MOSFET
on-resistance

CTRL = GND, 2.2V ≤ VIN ≤ 5.5V, ILOAD = - 10mA

TA = 25°C

40

TA = –40°C to 85°C

65
100
1010

Ω
nA

LOAD OUTPUT (LOAD)

tRise_LOAD

VLOAD rise time

Ω

0.6

1.25

30

65

315

800

µs

170

250

340

mV

110

200

280

Starting with CTRL low to high transition, time to ramp VLOAD from 0V
to 95% VOUT = 1.8V, 2.2V ≤ VIN ≤ 5.5V, ILOAD = 1mA

AUTO 100% MODE TRANSITION
VTH_100+

Auto 100% Modeleave detection
threshold (1)Rising VIN,100% Mode is left with VIN = VOUT + VTH_100+ , max value at
TJ = 85°C

VTH_100-

Auto 100% Mode
enter detection
threshold (1)Falling VIN, 100% Mode is entered with VIN = VOUT + VTH_100-, maxvalue at TJ = 85°C

POWER GOOD OUTPUT (PG, OPEN DRAIN)
VTH_PG+Power goodthreshold voltage

Rising output voltage on VOUT pin, referred to VVOUT

Low level output
voltage

2.2V ≤ VIN ≤ 5.5V, EN = GND, current into PG pin IPG = 4mA

Bias current into
PG pinPG pin is high impedance, VOUT = 2V, EN =VIN, CTRL = GND, IOUT = 0mA

tONminMinimum ON time

VIN = 3.6V, VOUT = 2.0V, IOUT = 0 mA

tOFFmin

Minimum OFF time VIN = 2.3V

50

tStartup_delay

Regulator start up
delay time

VIN = 3.6V, from transition EN = low to high until device starts switching

10

25

ms

tSoftstart

Softstart time with
reduced switch
current limit

2.2V ≤ VIN ≤ 5.5V, EN = VIN

700

1200

µs

ILIM_softstartHigh side
MOSFET switch
current limit

Reduced switch current limit during softstart

150

200

mA

3.3

V

VPG_HysVOL
IIN_PG

97.5%

Hysteresis

-3%
0.3

TA = 25°C

0

TA = –40°C to 85°C

10

V
nA

25

OUTPUT
225

TPS62740

80

TPS62742

(1)

6

ns

150

Low side MOSFET
switch current limit

VVOUT

ns

150

Output voltage
range

Output voltages are selected with pins VSEL 1 - 4

1.8

Output voltage
accuracy

VIN = 3.6V, IOUT = 10mA, VOUT = 1.8V

-2.5

0%

2.5

VIN = 3.6V, IOUT = 100mA, VOUT = 1.8V

–2

0%

2

DC output voltage
load regulation

VOUT = 1.8V, VIN = 3.6V, CTRL = VIN

DC output voltage
line regulation

VOUT = 1.8V, CTRL = VIN, IOUT = 10 mA, 2.5V ≤ VIN ≤ 5.5V

0.001

%/mA

0

%/V

VIN is compared to the programmed output voltage (VOUT). When VIN–VOUT falls below VTH_100- the device enters 100% Mode by turning
the high side MOSFET on. The 100% Mode is exited when VIN–VOUT exceeds VTH_100+ and the device starts switching. The hysteresis
for the 100% Mode detection threshold VTH_100+ - VTH_100- will always be positive and will be approximately 50 mV(typ.)

Submit Documentation Feedback

Copyright © 2013–2014, Texas Instruments Incorporated

TPS62740, TPS62742
www.ti.com

SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

8.6 Typical Characteristics
1000
900

TA = −40°C
TA = 25°C
TA = 60°C
TA = 85°C

TA = −40°C
TA = 25°C
TA = 60°C
TA = 85°C

400

700

Shutdown Current ISD (nA)

Quiescent Current Iq (nA)

800

500

600
500
400
300
200

300

200

100

100
0
2.0

2.5

3.0

3.5
4.0
4.5
Input Voltage VIN (V)EN = VIN, VOUT = 1.8V, CTRL = GND

5.0

0
2.0

5.5

Device Not Switching

2.5

3.0

3.5
4.0
4.5
Input Voltage VIN (V)

5.0

5.5

EN = GND

Figure 1. Quiescent Current

Figure 2. Shutdown Current ISD
1.0
0.9

TA = −40°C
TA = 25°C
TA = 60°C
TA = 85°C

0.8
0.7
0.6
0.5
0.4
0.3
TA = -40°C
TA = 25°C
TA = 60°C
TA = 85°C

0.2
0.1
0.0
2.0

2.5

3.0

3.5
4.0
4.5
Input Voltage VIN (V)

5.0

5.5

Figure 4. RDSON Low Side Mosfet

Figure 3. RDSON High Side Mosfet
1.2
1.1
1.0
0.9
0.8

RLOAD (W)

0.7
0.6
0.5
0.4
0.3

TA = −40°C
TA = 25°C
TA = 60°C
TA = 85°C

0.2
0.1
0.0
1.8

2.2

2.6
3.0
Output Voltage VOUT (V)

3.4

Figure 5. Load Switch Resistance RLOAD

Copyright © 2013–2014, Texas Instruments Incorporated

Submit Documentation Feedback

7

TPS62740, TPS62742
SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

www.ti.com

9 Detailed Description
9.1 Overview
The TPS6274x is the first step down converter with an ultra low quiescent current consumption (360nA typ.) andfeaturing TI's DCS-Control™ topology while maintaining a regulated output voltage. The device extends highefficiency operation to output currents down to a few micro amperes.

9.2 Functional Block Diagram
PG

CTRL

VOUT
EN

Ultra Low Power
Reference VREF = 1.2V

Softstart

PG Comp
VFB

UVLO

VOUT
Discharge

EN

VTH_PGVOUTVSEL 1

Load Switch

Internal
VFB feedback
divider
network*

VSEL 2
VSEL 3
VSEL 4

UVLO
Comp
VIN

UVLO

Auto 100% Mode
Comp
100%
VIN
Mode

Current
Limit Comparator

Timer
VIN
VOUT

LOAD

VTH_100

VTH_UVLO

DCSControl

Slew Rate
CTRL
Control
EN
UVLO Discharge

Min. On

UVLO

Limit
High SidePower Stage
VIN
PMOS

Min. OFF

VOUT

Direct Control& Compensation

EN

Control
Logic

Gate Driver
Anti
Shoot-Through

SW

VFB
VREF

Error
amplifier

Main
Comparator

Limit
Low Side
Current
Limit Comparator

NMOS
GND

* typical 50MW

9.3 Feature Description
9.3.1 DCS-Control™
TI's DCS-Control™ (Direct Control with Seamless Transition into Power Save Mode) is an advanced regulation
topology, which combines the advantages of hysteretic and voltage mode control. Characteristics of DCSControl™ are excellent AC load regulation and transient response, low output ripple voltage and a seamless
transition between PFM and PWM mode operation. DCS-Control™ includes an AC loop which senses the output
voltage (VOUT pin) and directly feeds the information to a fast comparator stage. This comparator sets theswitching frequency, which is constant for steady state operating conditions, and provides immediate response to
dynamic load changes. In order to achieve accurate DC load regulation, a voltage feedback loop is used. Theinternally compensated regulation network achieves fast and stable operation with small external components
and low ESR capacitors.

8

Submit Documentation Feedback

Copyright © 2013–2014, Texas Instruments Incorporated

TPS62740, TPS62742
www.ti.com

SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

Feature Description (continued)
The DCS-Control™ topology supports PWM (Pulse Width Modulation) mode for medium and high loadconditions and a Power Save Mode at light loads. During PWM mode, it operates in continuous conduction. The
switching frequency is up to 2MHz with a controlled frequency variation depending on the input voltage. If theload current decreases, the converter seamlessly enters Power Save Mode to maintain high efficiency down tovery light loads. In Power Save Mode the switching frequency varies nearly linearly with the load current. Since
DCS-Control™ supports both operation modes within one single building block, the transition from PWM toPower Save Mode is seamless without effects on the output voltage. The TPS6274x offers both excellent DC
voltage and superior load transient regulation, combined with very low output voltage ripple, minimizing
interference with RF circuits. At high load currents, the converter operates in quasi fixed frequency PWM mode
operation and at light loads, in PFM (Pulse Frequency Modulation) mode to maintain highest efficiency over thefull load current range. In PFM Mode, the device generates a single switching pulse to ramp up the inductor
current and recharge the output capacitor, followed by a sleep period where most of the internal circuits are
shutdown to achieve a lowest quiescent current. During this time, the load current is supported by the output
capacitor. The duration of the sleep period depends on the load current and the inductor peak current.
During the sleep periods, the current consumption of TPS6274x is reduced to 360nA. This low quiescent current
consumption is achieved by an ultra low power voltage reference, an integrated high impedance (typ. 50MΩ)
feedback divider network and an optimized DCS-Control™ block.
9.3.2 CTRL / Output Load
With the CTRL pin set to high, the LOAD pin is connected to the VOUT pin via an load switch and can power up
an additional, temporarily used sub-system. The load switch is slew rate controlled to support soft switching andnot to impact the regulated output VOUT. If CTRL pin is pulled to GND, the LOAD pin is disconnected from the
VOUT pin and internally connected to GND by an internal discharge switch. When CTRL pin is set to high, theQuiescent current of the DCS control block is increased to typ. 12.5µA. This ensures excellent transient response
on both outputs VOUT and LOAD in case of a sudden load step at the LOAD output. The CTRL pin can becontrolled by a micro controller.
9.3.3 Enable / Shutdown
The DC/DC converter is activated when the EN pin is set to high. For proper operation, the pin must be
terminated and must not be left floating. With the EN pin set to low, the device enters shutdown mode with lessthan typ. 70nA current consumption.
9.3.4 Power Good Output (PG)
The Power Good comparator features an open drain output. The PG comparator is active with EN pin set to highand VIN is above the threshold VTH_UVLO+. It is driven to high impedance once VOUT trips the threshold VTH_PG+ forrising VOUT. The output is pulled to low level once VOUT falls below the PG hysteresis, VPG_hys. The output is also
pulled to low level in case the input voltage VIN falls below the undervoltage lockout threshold VTH_UVLO- or thedevice is disabled with EN = low. The power good output (PG) can be used as an indicator for the system tosignal that the converter has started up and the output voltage is in regulation.
9.3.5 Output Voltage Selection (VSEL1 – 4)
The TPS6274x doesn't require an external resistor divider network to program the output voltage. The device
integrates a high impedance (typ. 50MΩ) feedback resistor divider network which is programmed by the pins
VSEL 1-4. TPS6274x supports an output voltage range of 1.8V to 3.3V in 100mV steps. The output voltage canbe changed during operation and supports a simple dynamic output voltage scaling, shown in Figure 47. The
output voltage is programmed according to table Table 1.
9.3.6 Softstart
When the device is enabled, the internal reference is powered up and after the startup delay time tStartup_delay has
expired, the device enters softstart, starts switching and ramps up the output voltage. During softstart the device
operates with a reduced current limit, ILIM_softstart, of typ. 1/4 of the nominal current limit. This reduced current limit
is active during the softstart time tSoftstart. The current limit is increased to its nominal value, ILIMF, once thesoftstart time has expired.

Copyright © 2013–2014, Texas Instruments Incorporated

Submit Documentation Feedback

9

TPS62740, TPS62742
SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

www.ti.com

Feature Description (continued)
9.3.7 Undervoltage Lockout UVLO
The device includes an under-voltage lockout (UVLO) comparator which prevents the device from misoperation
at too low input voltages. The UVLO comparator becomes active once the device is enabled with EN set to high.
Once the input voltage trips the UVLO threshold VTH_UVLO+ (typically 2.075V) for rising VIN, the UVLO comparator
releases the device for start up and operation. With a falling input voltage, the device operates down to the
UVLO threshold level VTH_UVLO- (typically 1.925V). Once this threshold is tripped, the device stops switching, theload switch at pin LOAD is disabled and both rails, VOUT and LOAD are discharged. The converter starts
operation again once the input voltage trips the rising UVLO threshold level VTH_UVLO+.

9.4 Device Functional Modes
9.4.1 VOUT And LOAD Output Discharge
Both the VOUT pin and the LOAD pin feature a discharge circuit to connect each rail to GND, once they are
disabled. This feature prevents residual charge voltages on capacitors connected to these pins, which may
impact proper power up of the main- and sub-system. With CTRL pin pulled to low, the discharge circuit at theLOAD pin becomes active. With the EN pin pulled to low, the discharge circuits at both pins VOUT and Load are
active. The discharge circuits of both rails VOUT and LOAD are associated with the UVLO comparator as well.
Both discharge circuits become active once the UVLO comparator triggers and the input voltage VIN has dropped
below the UVLO comparator threshold VTH_UVLO- (typ. 1.925V).
9.4.2 Automatic Transition Into 100% Mode
Once the input voltage comes close to the output voltage, the DC/DC converter stops switching and enters 100%
duty cycle operation. It connects the output VOUT via the inductor and the internal high side MOSFET switch tothe input VIN, once the input voltage VIN falls below the 100% mode enter threshold, VTH_100-. The DC/DC
regulator is turned off, not switching and therefore it generates no output ripple voltage. Because the output isconnected to the input, the output voltage tracks the input voltage minus the voltage drop across the internal highside switch and the inductor caused by the output current. Once the input voltage increases and trips the 100%mode leave threshold, VTH_100+ , the DC/DC regulator turns on and starts switching again. See Figure 6,
Figure 49, Figure 50, Figure 51.
VIN

VIN,
VOUT

100%
Mode
100%
Mode

VTH_100+
VTH_100VOUT
tracks VIN

VTH_PG+

Step Down Operation

VOUT
tracks VIN

VPG_Hys

VUVLO+VUVLOVOUT
discharge

tsoftstart

PG
High

Low

Low

Figure 6. Automatic 100% Mode Transition

10

Submit Documentation Feedback

Copyright © 2013–2014, Texas Instruments Incorporated

TPS62740, TPS62742
www.ti.com

SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

Device Functional Modes (continued)
9.4.3 Internal Current Limit
The TPS6274x integrates a current limit on the high side, as well the low side MOSFETs to protect the device
against overload or short circuit conditions. The peak current in the switches is monitored cycle by cycle. If thehigh side MOSFET current limit is reached, the high side MOSFET is turned off and the low side MOSFET isturned on until the current decreases below the low side MOSFET current limit.
9.4.4 Dynamic Voltage Scaling with VSEL Interface
During operation, the output voltage of the device can be changed, see Figure 47. The device will not actively
ramp down the output voltage from a higher to a lower level.

Copyright © 2013–2014, Texas Instruments Incorporated

Submit Documentation Feedback

11

TPS62740, TPS62742
SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

www.ti.com

10 Application and Implementation
10.1 Application Information
The TPS6274x devices are a step down converter family featuring typ. 360nA quiescent current and operatingwith a tiny 2.2µH inductor and 10µF output capacitor. This new DCS-ControlTM based devices extend the lightload efficiency range below 10µA load currents. TPS62740 supports output currents up to 300mA, TPS62742 up
to 400mA. The devices operate from rechargeable Li-Ion batteries, Li-primary battery chemistries such as LiSOCl2, Li-MnO2 and two or three cell alkaline batteries.

10.2 Typical Application

CIN
10mF

TPS62740
VIN
EN
VSEL1
VSEL2
VSEL3
VSEL4
GND

SW
VOUT

2.1V
L 2.2mH Main rail

Rpull up
PG
CTRL
LOAD

VCC

Low Power
MCU + RF

VIN
2.2V - 5.5V

COUT
10mF

Switched
supply rail
VCC

Subsystem(Sensors)

VIN
4V - 5.5V
CIN
10mF

TPS62742
VIN
EN
VSEL1
VSEL2
VSEL3
VSEL4
GND

SW
VOUT

3.3V
L 2.2mH 400mA

Rpull up
PG
CTRL
LOAD

VCC

COUT
10mF

Main System

Figure 7. TPS62740 Typical Application Circuit

Switched
supply rail
VCC

Subsystem
Figure 8. TPS62742 Typical Application Circuit
10.2.1 Design Requirements
The TPS6274x is a highly integrated DC/DC converter. The output voltage is set via a VSEL pin interface without
any additional external components. For proper operation only a input- and output capacitor and an inductor isrequired. The integrated load switch doesn't require a capacitor on its LOAD pin. Table 2 shows the components
used for the application characteristic curves.
Table 2. Components for Application Characteristic Curves
Reference

Description

TPS62740/42

360nA Iq step down converter

CIN, COUT, CLOAD

Ceramic capacitor GRM188R60J106M

10µF

MurataL

Inductor LPS3314

2.2µH

Coilcraft

12

Submit Documentation Feedback

Value

Manufacturer
Texas Instruments

Copyright © 2013–2014, Texas Instruments Incorporated

TPS62740, TPS62742
www.ti.com

SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

10.2.2 Detailed Design Procedure
Table 3 shows the recommended output filter components. The TPS6274x is optimized for operation with a
2.2µH inductor and with 10µF output capacitor.
Table 3. Recommended LC Output Filter Combinations
Inductor Value [µH] (1)Output Capacitor Value [µF] (2)
4.7µF

10µF

22µF

√

√ (3)

√

2.2
(1)
(2)
(3)

Inductor tolerance and current de-rating is anticipated. The effective inductance can vary by 20% and 30%.
Capacitance tolerance and bias voltage de-rating is anticipated. The effective capacitance can vary by
20% and -50%.
This LC combination is the standard value and recommended for most applications.

10.2.2.1 Inductor Selection
The inductor value affects its peak-to-peak ripple current, the PWM-to-PFM transition point, the output voltage
ripple and the efficiency. The selected inductor has to be rated for its DC resistance and saturation current. The
inductor ripple current (ΔIL) decreases with higher inductance and increases with higher VIN or VOUT and can be
estimated according to Equation 1.
Equation 2 calculates the maximum inductor current under static load conditions. The saturation current of theinductor should be rated higher than the maximum inductor current, as calculated with Equation 2. This is
recommended because during a heavy load transient the inductor current rises above the calculated value. A
more conservative way is to select the inductor saturation current above the high-side MOSFET switch current
limit, ILIMF.
Vout
1Vin
D IL = Vout ´
L ´ ¦
(1)
ILmax = Ioutmax +

DIL
2

(2)

With:
f = Switching Frequency
L = Inductor Value
ΔIL= Peak to Peak inductor ripple current
ILmax = Maximum Inductor current
In DC/DC converter applications, the efficiency is essentially affected by the inductor AC resistance (i.e. quality
factor) and by the inductor DCR value. Increasing the inductor value produces lower RMS currents, but degrades
transient response. For a given physical inductor size, increased inductance usually results in an inductor withlower saturation current.
The total losses of the coil consist of both the losses in the DC resistance (RDC) and the following frequencydependent components:• The losses in the core material (magnetic hysteresis loss, especially at high switching frequencies)• Additional losses in the conductor from the skin effect (current displacement at high frequencies)• Magnetic field losses of the neighboring windings (proximity effect)• Radiation losses

Copyright © 2013–2014, Texas Instruments Incorporated

Submit Documentation Feedback

13

TPS62740, TPS62742
SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

www.ti.com

The following inductor series from different suppliers have been used:
Table 4. List Of Inductors (1)(1)

INDUCTANCE [µH]

DIMENSIONS [mm3]

INDUCTOR TYPE

SUPPLIER

2.2

3.3 x 3.3 x 1.4

LPS3314

Coilcraft

2.2

2.5 x 3.0 x 1.5

VLF302515MT

TDK

2.2

2.0 × 1.2 × 1.0

MIPSZ2012 2R2

FDK

2.2

2.5 x 2.0 x 1.2

MIPSA2520 2R2

FDK

2.2

2.0 x 1.2 x 1.0

MDT2012CH2R2

TOKO

See Third-party Products Disclaimer

10.2.2.2 DC/DC Output Capacitor Selection
The DCS-Control™ scheme of the TPS6274x allows the use of tiny ceramic capacitors. Ceramic capacitors withlow ESR values have the lowest output voltage ripple and are recommended. The output capacitor requires
either an X7R or X5R dielectric. Y5V and Z5U dielectric capacitors, aside from their wide variation in capacitanceover temperature, become resistive at high frequencies. At light load currents, the converter operates in Power
Save Mode and the output voltage ripple is dependent on the output capacitor value and the PFM peak inductor
current. A larger output capacitors can be used, but it should be considered that larger output capacitors lead toan increased leakage current in the capacitor and may reduce overall conversion efficiency. Furthermore, larger
output capacitors impact the start up behavior of the DC/DC converter.
10.2.2.3 Input Capacitor Selection
Because the buck converter has a pulsating input current, a low ESR input capacitor is required for best input
voltage filtering to ensure proper function of the device and to minimize input voltage spikes. For mostapplications a 10µF is sufficient. The input capacitor can be increased without any limit for better input voltage
filtering.
Table 5 shows a list of tested input/output capacitors.
Table 5. List Of Capacitors (1)

(1)

14

CAPACITANCE [μF]

SIZE

CAPACITOR TYPE

SUPPLIER

100603

GRM188R60J106ME84

MurataSee Third-party Products Disclaimer

Submit Documentation Feedback

Copyright © 2013–2014, Texas Instruments Incorporated

TPS62740, TPS62742
www.ti.com

SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

10.2.3 Application Curves
95.0

95

90.0

90

85.0

85

80.0

80
75

VIN = 2.7V
VIN = 3.3V
VIN = 3.6V
VIN = 4.2V
VIN = 5.0V

70.0
65.0

Efficiency (%)

Efficiency (%)

75.0

70
65

60.0

60

55.0

55

50.0

50

45.0

45

40.0
0.001

0.01

0.1
1
10
Output Current (mA)

COUT = 10 µF (0603)

VIN = 2.7V
VIN = 3.3V
VIN = 3.6V
VIN = 4.2V
VIN = 5.0V

100

40
0.001

1000

CTRL = GND
L = 2.2 µH (LPS3314 2R2)

COUT = 10 µF (0603)

Figure 9. Efficiency VOUT = 1.8V

0.1
1
10
Output Current (mA)

100

1000

CTRL = GND
L = 2.2 μH (LPS3314 2R2)

Figure 10. Efficiency VOUT = 2.1V

100

100

95

95

90

90

85

85

80

VIN = 3.6V

75

VIN = 4.2V
VIN = 5.0V

70

VIN = 3.0V
VIN = 3.3V
VIN = 3.6V
VIN = 4.2V
VIN = 5.0V

80

Efficiency (%)

Efficiency (%)

0.01

65
60

75
70
65
60

55

55

50

50

45

45

40
0.001

0.01

0.1

1

10

40
0.001

100

0.01

Output Current IOUT (mA)
C001

COUT = 10 µF,

CTRL = GND.
L = 2.2 µH (VLF302515)

COUT = 10 µF (0603)

0.1
1
10
Output Current (mA)

100

1000

CTRL = GND
L = 2.2 µH (LPS3314 2R2)

Figure 12. Efficiency VOUT = 2.5V

Figure 11. Efficiency VOUT = 3.3V TPS62742
100

100
95

90

90
85

80

VIN = 3.6V
VIN = 4.2V
VIN = 5.0V

75

Efficiency (%)

Efficiency (%)

80

70
65

70

60

60
50

55
50

40

45
40
0.001

30

0.01

0.1
1
10
Output Current (mA)

COUT = 10 µF (0603)

100

1000

CTRL = GND
L = 2.2 µH (LPS3314 2R2)

Figure 13. Efficiency VOUT = 3.3V

Copyright © 2013–2014, Texas Instruments Incorporated

2

IOUT = 1mA
IOUT = 2mA
IOUT = 5mA
IOUT = 10mA
IOUT = 100mA
IOUT = 50mA
IOUT = 200mA
2.5
3
3.5
4
4.5
Input Voltage VIN (V)

COUT = 10 µF (0603)

55.5

CTRL = GND
L = 2.2 µH (LPS3314 2R2)

Figure 14. Efficiency VOUT = 1.8V

Submit Documentation Feedback

15

TPS62740, TPS62742
SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

www.ti.com

100

100

90

90

80
80

60

Efficiency (%)

Efficiency (%)

70

50
IOUT = 1mA
IOUT = 2mA
IOUT = 5mA
IOUT = 10mA
IOUT = 100mA
IOUT = 1mA
IOUT = 10mA
IOUT = 50mA
IOUT = 200mA

40
30
20
10
0

2

2.5

3

60
IOUT = 1mA
IOUT = 2mA
IOUT = 5mA
IOUT = 10mA
IOUT = 100mA
IOUT = 1mA
IOUT = 10mA
IOUT = 50mA
IOUT = 200mA

50
40
30

3.5
4
Input Voltage VIN (V)

COUT = 10 µF (0603)

70

4.5

5

20
2.5

5.5

CTRL = GND
L = 2.2 µH (LPS3314 2R2)

3

COUT = 10 µF (0603)

Figure 15. Efficiency VOUT = 2.1V

3.5
4
4.5
Input Voltage VIN (V)5

5.5

CTRL = GND
L = 2.2 µH (LPS3314 2R2)

Figure 16. Efficiency VOUT = 2.5V
1.854

100
90

1.836

Output Voltage VOUT (V)Efficiency (%)

80
70
60
IOUT = 1mA
IOUT = 2mA
IOUT = 5mA
IOUT = 10mA
IOUT = 100mA
IOUT = 1mA
IOUT = 10mA
IOUT = 50mA
IOUT = 200mA

50
40
30
20
3.5

4

COUT = 10 µF (0603)

1.818

1.8

1.782

4.5
Input Voltage VIN (V)

5

1.746
0.001

5.5

CTRL = GND
L = 2.2 µH (LPS3314 2R2)

2.142

2.55

2.121

2.525

2.1

2.079
VIN = 2.7V
VIN = 3.3V
VIN = 3.6V
VIN = 4.2V
VIN = 5.0V
0.01

COUT = 10 µF (0603)

0.1
1
10
Output Current IOUT (mA)

100

1000

CTRL = GND
L = 2.2 µH (LPS3314 2R2)

Figure 19. Output Voltage VOUT = 2.1V

16

Submit Documentation Feedback

0.1
1
10
Output Current IOUT (mA)

100

1000

CTRL = GND
L = 2.2 µH (LPS3314 2R2)

Figure 18. Output Voltage VOUT = 1.8V
2.575

Output Voltage VOUT (V)Output Voltage VOUT (V)Figure 17. Efficiency VOUT = 3.3V

2.058

0.01

COUT = 10 µF (0603)

2.163

2.037
0.001

VIN = 2.7V
VIN = 3.3V
VIN = 3.6V
VIN = 4.2V
VIN = 5.0V

1.764

2.5

2.475

VIN = 3.3V
VIN = 3.6V
VIN = 4.2V
VIN = 5.0V

2.45

2.425
0.001

0.01

COUT = 10 µF (0603)

0.1
1
10
Output Current IOUT (mA)

100

1000

CTRL = GND
L = 2.2 µH (LPS3314 2R2)

Figure 20. Output Voltage VOUT = 2.5V

Copyright © 2013–2014, Texas Instruments Incorporated

TPS62740, TPS62742
www.ti.com

SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014
3.399

2000

Switching Frequency (kHz)Output Voltage VOUT (V)

3.366

3.333

3.3

3.267

1500

1000

VIN = 2.5V
VIN = 3.0V
VIN = 3.6V
VIN = 4.2V
VIN = 5.0V

500

3.234

VIN = 3.6V
VIN = 4.2V
VIN = 5.0V

3.201
0.001

0.01

0.1
1
10
Output Current IOUT (mA)

COUT = 10 µF (0603)

100

0

1000

CTRL = GND
L = 2.2 µH (LPS3314 2R2)

Figure 21. Output Voltage VOUT = 3.3V

50

100

300

L = 2.2 µH

Figure 22. Typical Switching Frequency VOUT = 1.8V

Switching Frequency (kHz)

1500

35
30
25
20
15

1000

500

VIN = 2.7V
VIN = 3.0V
VIN = 3.6V
VIN = 4.2V
VIN = 5.0V

10
5

0

50

100

150

200

250

0

300

0

50

100

150

200

250

300

Output Current (mA)

Output Current (mA)

COUT = 10 µF (0603)

CTRL = GND
L = 2.2 µH

Figure 23. Typical Output Ripple Voltage VOUT = 1.8V

COUT = 10 µF

L = 2.2 µH

Figure 24. Typical Switching Frequency VOUT = 2.1V
2500

50
VIN = 2.7V
VIN = 3.0V
VIN = 3.6V
VIN = 4.2V
VIN = 5.0V

45
40

2000

Switching Frequency (kHz)VOUTpp peak to peak Output Ripple Voltage (mVpp)

250

2000

40

35
30
25
20
15
10

1500

1000

VIN = 3.6V
VIN = 4.2V
VIN = 5.0V

500

5
0

200

COUT = 10 µF

VIN = 2.7V
VIN = 3.0V
VIN = 3.6V
VIN = 4.2V
VIN = 5.0V

45

0

150

Output Current (mA)50

VOUTpp peak to peak Output Ripple Voltage (mVpp)

0

0

50

100

150

200

250

300

0

0

COUT = 10 µF (0603)

CTRL = GND
L = 2.2 µH

Figure 25. Typical Output Ripple Voltage VOUT = 2.1V

Copyright © 2013–2014, Texas Instruments Incorporated

50

100

150

200

250

300

Output Current (mA)

Output Current (mA)

COUT = 10 µF

L = 2.2 µH

Figure 26. Typical Switching Frequency VOUT = 3.0V

Submit Documentation Feedback

17

TPS62740, TPS62742
www.ti.com
2.50

50
VIN = 3.6V
VIN = 4.2V
VIN = 5.0V

45
40

2.40

35

2.35

30
25
20
15

2.30
2.25
2.20
2.15

10

2.10

5

2.05

0

0

50

IOUT = 10mA, rising VIN
IOUT = 10mA, falling VIN
IOUT = 50mA, rising VIN
IOUT = 50mA, falling VIN
IOUT = 100mA, rising VIN
IOUT = 100mA, falling VIN

2.45

Output Voltage VOUT (V)VOUTpp peak to peak Output Ripple Voltage (mVpp)

SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

100

150

200

250

2.00
2.20

300

2.25

COUT = 10 µF (0603)

2.50

3.60
3.55

IOUT = 10mA, rising VIN
IOUT = 10mA, falling VIN
IOUT = 50mA, rising VIN
IOUT = 50mA, falling VIN
IOUT = 100mA, rising VIN
IOUT = 100mA, falling VIN

3.50
3.45

2.70
2.65
2.60
2.55

3.40
3.35
3.30
3.25

IOUT = 10mA, rising VIN
IOUT = 10mA, falling VIN
IOUT = 50mA, rising VIN
IOUT = 50mA, falling VIN
IOUT = 100mA, rising VIN
IOUT = 100mA, falling VIN

3.20
3.15

2.50

3.10

2.45

3.05

2.40
2.40 2.45 2.50 2.55 2.60 2.65 2.70 2.75 2.80 2.85 2.90

3.00
3.20

3.30

L = 2.2 µH (LPS3314)
Figure 29. 100% Mode Transition VOUT 2.5V

VIN = 3.6 V

IOUT = 10 µA
COUT = 10 µF

L = 2.2 µH
CTRL = GND

Figure 31. Typical Operation ILoad = 10µA VOUT = 1.8V

Submit Documentation Feedback

3.40

3.50

3.60

3.70

Input Voltage VIN (V)Input Voltage VIN (V)

18

2.45

Figure 28. 100% Mode Transition VOUT 2.1V

Output Voltage VOUT (V)Output Voltage VOUT (V)

2.75

2.40

L = 2.2 µH (LPS3314)

2.90

2.80

2.35

CTRL = GND
L = 2.2 µH

Figure 27. Typical Output Ripple Voltage VOUT = 3.0V

2.85

2.30

Input Voltage VIN (V)Output Current (mA)

L = 2.2 µH (LPS3314)
Figure 30. 100% Mode Transition VOUT 3.3V

VIN = 3.6 V
COUT = 10 µF

IOUT = 1 mA

L = 2.2 µH
CTRL = GND

Figure 32. Typical Operation ILoad = 1ma, VOUT = 1.8V

Copyright © 2013–2014, Texas Instruments Incorporated

TPS62740, TPS62742
www.ti.com

SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

VIN = 3.6 V
COUT = 10 µF

IOUT = 25 mA

L = 2.2 µH
CTRL = GND

Figure 33. Typical Operation ILoad = 25mA, VOUT = 1.8V

VIN = 3.6 V

IOUT = 50 µA to 10 mA
COUT = 10 µF

L = 2.2 µH
CTRL = GND

Figure 35. Load Transient Response VOUT = 1.8V

VIN = 3.6 V, VOUT = 2.1 V

L = 2.2 µH
COUT = 10 µF
Loadstep at VOUT 0 mA to 100 mA,
1 µs rise/ fall time, 70 µs / 7 ms

Figure 37. Load Transient Response CTRL = GND

Copyright © 2013–2014, Texas Instruments Incorporated

VIN = 3.6 V

IOUT = 150 mA
COUT = 10 µF

L = 2.2 µH
CTRL = GND

Figure 34. Typical Operation ILoad = 150ma, VOUT = 1.8V

VIN = 3.6 V

IOUT = 0.5 mA to 150 mA
COUT = 10 µF

L = 2.2 µH
CTRL = VIN

Figure 36. Load Transient Response VOUT = 2.1V

VIN = 3.6 V, VOUT = 2.1 V

L = 2.2 µH,
COUT = 10 µF
Loadstep at VOUT 0 mA to 100 mA,
1 µs rise/fall time; 70 µs / 7 ms

Figure 38. Load Transient Response CTRL = VIN

Submit Documentation Feedback

19

TPS62740, TPS62742
SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

VIN = 3.6 V / 4.2 V

www.ti.com

VOUT = 2.1 V
COUT = 10 µF

L = 2.2 µH
CTRL = GND

Figure 39. Line Transient Response IOUT=10mA

VIN = 3.6 V

IOUT = 50 µA to 300 mA
COUT = 10 µF

L = 2.2 µH
CTRL = GND

Figure 41. AC Load Sweep VOUT = 2.1V

VLOAD slew rate
controlled

VOUT = 2.1 V
COUT = 10 µF

L = 2.2 µH
CTRL = GND

Figure 40. Line Transient Response IOUT = 100mA

VIN = 3.6 V,
IOUT = 0 mA
COUT = 10 µF

VOUT = VLOAD= 2.1 V
CTRL = VIN
CLOAD = 10 µF
L = 2.2 µH
ILOAD = 0 to 50 mA to 0 mA

Figure 42. Load Step At Load Output

VLOAD Discharge

VIN = 3.6 V
IOUT = 0 mA

VOUT = 2.1 V
COUT = 10 µF

ILOAD = 0 mA
CLOAD = 10 µF
L = 2.2 µH

Figure 43. Load Output On / Off

20

VIN = 3.6 V / 4.2 V

Submit Documentation Feedback

VIN = 3.6 V
ROUT = 100 Ω

VOUT = 2.1 V
COUT = 10 µF

CTRL = GND
L = 2.2 µH

Figure 44. Device Enable And Start Up

Copyright © 2013–2014, Texas Instruments Incorporated

TPS62740, TPS62742
www.ti.com

SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

VIN = 3.6 V
ROUT = 100 Ω

VOUT = 2.1 V
COUT = 10 µF

CTRL = GND
L = 2.2 µH

Figure 45. VOUT Ramp Up After Enable

VIN = 3.6 V
COUT = 10 µF
IOUT = 5 mA

CTRL = GND
L = 2.2 µH

Ramp up / Down
VSEL 3+4 toggled
VSEL 1+2 = GND

Figure 47. Dynamic Output Voltage Scaling
VOUT = 1.8V/3.0V

VIN = 3.6 V
ROUT = 100 Ω,
ILOAD = 0 mA

L = 2.2 µH
CTRL = GND
VIN = ramp up/down 0 V to 5 V, 150 ms,
Output resistance 50 Ω

Figure 49. Input Voltage Ramp Up/Down VOUT = 2.6V

Copyright © 2013–2014, Texas Instruments Incorporated

CTRL = VIN
L = 2.2 µH

Figure 46. VOUT Ramp Up With Activated Load Switch

COUT = 10 µF

L = 2.2 µH
CTRL = GND
VIN = ramp up/down 0 V to 5 V, 150 ms,
Output resistance 50 Ω

Figure 48. Input Voltage Ramp Up/Down
VOUT = 1.8V

100% mode operation,high side MOSFET turned on

COUT = 10 µF

VOUT = VLOAD = 2.1 V
COUT = CLOAD = 10 µF

100% mode operation,high side MOSFET turned on

COUT = 10 µF

L = 2.2 µH
CTRL = GND
VIN = ramp up/down 0 V to 5 V, 150 ms,
Output resistance 50 Ω

Figure 50. Input Voltage Ramp Up/Down VOUT = 3.3V

Submit Documentation Feedback

21

TPS62740, TPS62742
SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

www.ti.com

High side mosfet turned on
100% Mode
Leave / EnterVOUT = 3.0 V

COUT = 10 µF
L = 2.2 µH, CTRL = GND
VIN = ramp up /down 2.8 V to 3.7 V,
Output resistance 50 Ω

Figure 51. Enter/Leave 100% Mode Operation

10.3 System Example
VBAT

TPS62740
VSEL1
VIN
VSEL2

CIN
EN

VSEL3
VSEL4
PG
CTRL

Voltage
Selection

Power Good

VOUT Main
RPull Up

Control Sub-System

L

VOUT Main

SW
GND
VOUT

Main
SupplyMasterMCU

LOAD
Switched Supply
SubSystem

SensorRadio

Figure 52. Example Of Implementation In A Master MCU Based System

22

Submit Documentation Feedback

Copyright © 2013–2014, Texas Instruments Incorporated

TPS62740, TPS62742
www.ti.com

SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

11 Power Supply Recommendations
The power supply to the TPS6274x needs to have a current rating according to the supply voltage, output
voltage and output current of the TPS6274x.

12 Layout12.1 Layout Guidelines
As for all switching power supplies, the layout is an important step in the design. Care must be taken in board
layout to get the specified performance. If the layout is not carefully done, the regulator could show poor line
and/or load regulation, stability issues as well as EMI problems and interference with RF circuits. It is critical toprovide a low inductance, impedance ground path. Therefore, use wide and short traces for the main current
paths. The input capacitor should be placed as close as possible to the IC pins VIN and GND. The output
capacitor should be placed close between VOUT and GND pins. The VOUT line should be connected to the
output capacitor and routed away from noisy components and traces (e.g. SW line) or other noise sources. The
exposed thermal pad of the package and the GND pin should be connected. See Figure 53 for therecommended PCB layout.

12.2 Layout Example
VSEL
EN 1-4 PG
TPS62740
U1x9

U1x8

U1x7

GND
LOAD
C2x2

U1x4

U1x5

U1x6

U1x3

C1x1

C2x1

L1x2

CIN
(0603)

L1x1

VIN

C1x2

7.2 mm

U1x13

U1x12

U1x11

U1x10

U1x1

U1x2

GND

VOUT
COUT
(0603)

L(0805)
4.3 mm2
Solution size: 31mm
Height: 1mm max.
Figure 53. Recommended PCB Layout

Copyright © 2013–2014, Texas Instruments Incorporated

Submit Documentation Feedback

23

TPS62740, TPS62742
SLVSB02B – NOVEMBER 2013 – REVISED JULY 2014

www.ti.com

13 Device and Documentation Support
13.1 Device Support
13.1.1 Third-Party Products Disclaimer
TI'S PUBLICATION OF INFORMATION REGARDING THIRD-PARTY PRODUCTS OR SERVICES DOES NOTCONSTITUTE AN ENDORSEMENT REGARDING THE SUITABILITY OF SUCH PRODUCTS OR SERVICES
OR A WARRANTY, REPRESENTATION OR ENDORSEMENT OF SUCH PRODUCTS OR SERVICES, EITHERALONE OR IN COMBINATION WITH ANY TI PRODUCT OR SERVICE.

13.2 Documentation Support
13.2.1 Related Documentation
See also TPS62740EVM-186 Evaluation Module User's Guide, SLVU949; and application note Accurately
measuring efficiency of ultralow-IQ devices, SLYT558 for accurate efficiency measurements in PFM mode
operation.

13.3 Related Links
The table below lists quick access links. Categories include technical documents, support and community
resources, tools and software, and quick access to sample or buy.
Table 6. Related LinksPARTS

PRODUCT FOLDERSAMPLE & BUY

TECHNICALDOCUMENTS

TOOLS &SOFTWARE

SUPPORT &COMMUNITY

TPS62740

Click here

Click here

Click here

Click here

Click here

TPS62742

Click here

Click here

Click here

Click here

Click here

13.4 Trademarks
DCS-Control is a trademark of Texas Instruments.
Bluetooth is a registered trademark of Bluetooth SIG, Inc.

13.5 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.

13.6 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.

14 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the mostcurrent data available for the designated devices. This data is subject to change without notice and revision ofthis document. For browser-based versions of this data sheet, refer to the left-hand navigation.

24

Submit Documentation Feedback

Copyright © 2013–2014, Texas Instruments Incorporated

PACKAGE OPTION ADDENDUM

www.ti.com

5-Aug-2014

PACKAGING INFORMATION
Orderable Device

Status(1)

Package Type Package Pins Package
Drawing
Qty

Eco Plan

Lead/Ball Finish

MSL Peak Temp

(2)

(6)

(3)

Op Temp (°C)

Device Marking(4/5)

TPS62740DSSRACTIVE

WSON

DSS

12

3000

Green (RoHS& no Sb/Br)

CU NIPDAU

Level-2-260C-1 YEAR

-40 to 85

62740

TPS62740DSSTACTIVE

WSON

DSS

12

250

Green (RoHS& no Sb/Br)

CU NIPDAU

Level-2-260C-1 YEAR

-40 to 85

62740

TPS62742DSSRACTIVE

WSON

DSS

12

3000

Green (RoHS& no Sb/Br)

CU NIPDAU

Level-2-260C-1 YEAR

-40 to 85

62742

TPS62742DSSTACTIVE

WSON

DSS

12

250

Green (RoHS& no Sb/Br)

CU NIPDAU

Level-2-260C-1 YEAR

-40 to 85

62742

(1)

The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)

Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement thatlead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weightin homogeneous material)(3)

MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.

(4)

There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.

(5)

Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuationof the previous line and the two combined represent the entire Device Marking for that device.
(6)

Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.

Addendum-Page 1

SamplesPACKAGE OPTION ADDENDUM

www.ti.com

5-Aug-2014

Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken andcontinues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.

Addendum-Page 2

PACKAGE MATERIALS INFORMATION
www.ti.com

18-Aug-2014

TAPE AND REEL INFORMATION*All dimensions are nominal

DevicePackage Package Pins
Type Drawing

SPQ

Reel
Reel
A0
Diameter Width (mm)(mm) W1 (mm)TPS62740DSSR

WSON

DSS

12

3000

180.0

8.4

B0
(mm)

K0
(mm)

P1
(mm)

W
Pin1
(mm) Quadrant

2.25

3.25

1.05

4.0

8.0

Q1

TPS62740DSST

WSON

DSS

12

250

180.0

8.4

2.25

3.25

1.05

4.0

8.0

Q1

TPS62742DSSR

WSON

DSS

12

3000

180.0

8.4

2.25

3.25

1.05

4.0

8.0

Q1

TPS62742DSST

WSON

DSS

12

250

180.0

8.4

2.25

3.25

1.05

4.0

8.0

Q1

Pack Materials-Page 1

PACKAGE MATERIALS INFORMATION
www.ti.com

18-Aug-2014*All dimensions are nominal

DevicePackage Type

Package Drawing

Pins

SPQ

Length (mm)Width (mm)Height (mm)TPS62740DSSR

WSON

DSS

12

3000

210.0

185.0

35.0

TPS62740DSST

WSON

DSS

12

250

210.0

185.0

35.0

TPS62742DSSR

WSON

DSS

12

3000

210.0

185.0

35.0

TPS62742DSST

WSON

DSS

12

250

210.0

185.0

35.0

Pack Materials-Page 2

IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and otherchanges to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest
issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current andcomplete. All semiconductor products (also referred to herein as “components”) are sold subject to TI’s terms and conditions of salesupplied at the time of order acknowledgment.
TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms
and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary
to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily
performed.
TI assumes no liability for applications assistance or the design of Buyers’ products. Buyers are responsible for their products andapplications using TI components. To minimize the risks associated with Buyers’ products and applications, Buyers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, orother intellectual property right relating to any combination, machine, or process in which TI components or services are used. Information
published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or
endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of thethird party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alterationand is accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such altereddocumentation. Information of third parties may be subject to additional restrictions.
Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service
voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice.
TI is not responsible or liable for any such statements.
Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements
concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support
that may be provided by TI. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards whichanticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause
harm and take appropriate remedial actions. Buyer will fully indemnify TI and its representatives against any damages arising out of the useof any TI components in safety-critical applications.
In some cases, TI components may be promoted specifically to facilitate safety-related applications. With such components, TI’s goal is tohelp enable customers to design and create their own end-product solutions that meet applicable functional safety standards andrequirements. Nonetheless, such components are subject to these terms.
No TI components are authorized for use in FDA Class III (or similar life-critical medical equipment) unless authorized officers of the parties
have executed a special agreement specifically governing such use.
Only those TI components which TI has specifically designated as military grade or “enhanced plastic” are designed and intended for use inmilitary/aerospace applications or environments. Buyer acknowledges and agrees that any military or aerospace use of TI components
which have not been so designated is solely at the Buyer's risk, and that Buyer is solely responsible for compliance with all legal andregulatory requirements in connection with such use.
TI has specifically designated certain components as meeting ISO/TS16949 requirements, mainly for automotive use. In any case of use ofnon-designated products, TI will not be responsible for any failure to meet ISO/TS16949.
Products

Applications

Audio

www.ti.com/audio

Automotive and Transportation

www.ti.com/automotive

Amplifiers

amplifier.ti.com

Communications and Telecom

www.ti.com/communications

Data Converters

dataconverter.ti.com

Computers and Peripherals

www.ti.com/computers

DLP® Products

www.dlp.com

Consumer Electronics

www.ti.com/consumer-apps

DSP

dsp.ti.com

Energy and Lighting

www.ti.com/energy

Clocks and Timers

www.ti.com/clocks

Industrial

www.ti.com/industrial

Interfaceinterface.ti.com

Medicalwww.ti.com/medical

Logic

logic.ti.com

Security

www.ti.com/security

Power Mgmt

power.ti.com

Space, Avionics and Defense

www.ti.com/space-avionics-defense

Microcontrollers

microcontroller.ti.com

Video and Imaging

www.ti.com/video

RFID

www.ti-rfid.com

OMAP Applications Processors

www.ti.com/omap

TI E2E Community

e2e.ti.com

Wireless Connectivity

www.ti.com/wirelessconnectivity
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2014, Texas Instruments Incorporated