ELM7C377142xA CMOS voltage detector, 2 channels, 18V operation, reset hold by ext.C
http://www.elm-tech.com■General description

ELM7C377142xA is a 18V operation CMOS voltage detector for independent 2 lines power monitoring.
It detects abnormalities such as power supply voltage interruptions or drops, and generates a reset signal. Inaddition to the 5V power supply line, VSB input can work for the another power supply line detection, and a
reset signal is holded some period determined by an exterral capacitor.

■Features• Detection voltages with hysteresis function.
• A reference voltage output capability.
• Minimal external parts(one capacitor).
• Over voltage detection.
• Accurate voltage detection• Detection voltage adjustable with 2 external resistors• Monitoring of two power supply lines• Low voltage reset signal holding• Low power dissipation• Package: 4.2V±2.5%: 1.180V±1.5%: +5V and an arbitrary voltage: Typ.0.8V: Typ.65μA(Vcc=5V): SOP-8 150mil
SOP-8 208mil
SON8-3×3■Application• Reset for Microprocessor, etc.

■Maximum absolute ratings
ParameterPower supply
Input Voltage

SymbolLimitUnitVcc
Vsa
Vsb
Vsc20
Vss-0.3 to Vcc+0.3 (<+8.0)

VRESET output Voltage
OUTC output Voltage

VohPower dissipation

Pd

Operating temperature
Storage temperature

TopTstg

Vss-0.3 to +8.0
Vss-0.3 to Vcc+0.3 (<+5.5)
Vss-0.3 to +5.5
680 (SOP-8 150mil) *1
680 (SOP-8 208mil) *1
600 (SON8-3×3) * 2-40 to +85-55 to +150

VVmW°C°C* 1) When mounted on glass epoxy substrate with single layer FR4 70mm x 70mm x 1.6mm.
2) When mounted on 114.3mmx76.2mmx1.57mm 's two-layer FR4 glass epoxy board (based on EIA / JESD51-3/-5/-7).

Rev.2.2
1 / 12

ELM7C377142xA CMOS voltage detector, 2 channels, 18V operation, reset hold by ext.C
http://www.elm-tech.com■Selection guide
ELM7C377142xA-x
Symbola, bDetection voltage 42: Vsal=4.2V
D: SOP-8 150mil
P: SOP-8 208mil
G: SON8-3×3
Product version A
S: Refer to PKG file
Taping direction
N: Refer to PKG filec

ELM7C3771 4 2 x A - x↑↑↑ ↑ ↑a bc d ePackagede* The taping direction of SOP-8 (150mil) and SOP-8 (208mil) is N only.

■Pin configuration
SOP-8(TOP VIEW)
��

���

�

�

�

(BOTTOM VIEW) (BOTTOM VIEW)(TOP VIEW) VIEW)(TOP VIEW) SON8-3x3(BOTTOM
SON8-3x3(TOPVIEW)
87658

7655

6712341234485678321**3214* The potential of the tab on the back is the ground(GND) level.
Please connect to GND pin(recommended) or set it to be open.

Pin No. Pin nameDescription1CT
Power-on reset hold time setting capacitor connection pin
2VSC Comparator C plus input pin
345OUTC
GNDVCC

678VSBVSAComparator C inverted output pin
Ground pin
Power supply pin

Comparator B minus input pin
Comparator A minus input pin
RESET Outputs reset pin (negative logic)

Rev.2.2
2 / 12

ELM7C377142xA CMOS voltage detector, 2 channels, 18V operation, reset hold by ext.C■Standard circuit■Block diagram

http://www.elm-tech.com(Vreg)

5VCC
VSB

1Ct

2ELM7C377142xACTRESET

68CT1VCC(Vreg)

Q(Vreg)

VSC

Comp C

28(Vreg)(Vreg)

55k

VSA
71.180V

1.210V* The OUTC of pin3 and the VSA of pin7 are open.
* Please be careful that the input voltage of the VSB ofpin6 does not exceed the maximum absolute ratings. It
is recommended that the input voltage at the VSB pin
be less or equal than 6.5V.

135k

Comp A

4OUTC
3RESET

RS

RESET

GND

10uA(Vreg)

MicroController

VSC
GND(Vreg)12uA(Vreg)

Comp B

VSB
61.180V

VCC
5(Vreg)

GND
4ELM7C377142xAVoltage
Regulator■Functional descriptions
Comparators Comp.A and Comp.B apply a hysteresis to the detected voltage, so that when the voltage at either
the Vsa or Vsb pin falls below 1.180V the RESET output signal goes to “low” level.
Comp.B may be used to detect any given voltage(Application Circuit 3 : Arbitrary Voltage Supply Monitor),and can also be used as a forced reset pin (with reset hold time) with TTL input (Application Circuit 6 : 5V
Power Supply Monitor with forced RESET input (Vcc=5V) ). Note that if Comp.B is not used, the Vsb pinshould be connected to the Vcc pin (Application Circuit 1 : 5V Power Supply Monitor). Here, please be carefulthat the input voltage of the VSB pin does not exceed the maximum absolute ratings. It is recommended that theinput voltage at the VSB pin be less or equal than 6.5V.
Instantaneous breaks or drops in the power supply can be detected as abnormal conditions by theELM7C377142xA within a 2µs interval.However because momentary breaks or drops of this duration donot cause problems in actual systems in some cases, a delayed trigger function can be created by connecting
capacitors to the Vsa or Vsb pin (Application Circuit 9 : Supply Voltage Monitoring with Delayed Trigger).
Because the RESET output has built-in pull-up resistance, there is no need to connect to external pull-up
resistance when connected to a high impedance load such as a CMOS logic IC.
Comparator Comp.C is an open-drain output comparator without hysteresis, in which the polarity of input/
output characteristics is reversed. Thus Comp.C is useful for positive logic RESET signal output (Application
Circuit 8 : 5V Power Supply Monitor with Non-inverted RESET), as well as for creating a reference voltage(Application Circuit 7 : 1.210V Reference voltage generation and 5V monitoring). Note that if Comp. C is not
used, the Vsc pin should be connected to the GND pin (Application Circuit 1 : 5V Power Supply Monitor).
When VCC exceeds approximately 5.7 V, the internal circuit is regulated to this voltage.
Also, 5.7 V Zener diodes are built in at the output terminal and input terminal to protect the circuit.
Therefore, when VCC is 5.7 V or more, the H output level of RESET output terminal and OUTC output
terminal is 5.7 V instead of applied VCC level.
Rev.2.2
3 / 12

ELM7C377142xA CMOS voltage detector, 2 channels, 18V operation, reset hold by ext.C
http://www.elm-tech.com■Electrical characteristics
Parameter
Supply voltage
Power supply current

Detection voltage
Hysteresis width
Detection voltage
Deviation of detection voltage
Hysteresis width
Input current
Output voltage
Output sink current
Ct charge current
Input current
Detection voltage
Deviation of detection voltageOutput leakage current
Output voltage
Output sink current

Vcc=5.0V, Top=25°C
SymbolCondition
Vcc
Icc1 Vsb=5.0V, Vsc=0.0V
Icc2 Vsb=0.0V, Vsc=0.0V
Vcc falling
Vsal
Top=-40°C to +85°C
Vcc rising
Vsah
Top=-40°C to +85°C
Vhysa Vsah-Vsal
Vsb falling
Vsb
Top=-40°C to +85°C
ΔVsb Vcc=3.5V to 6.0V
Vhysb
Iihb Vsb=5.0V
Iilb Vsb=0.0V
Vohr Ireset=-5μA, Vsb=5.0V
Ireset=3mA, Vsa=0.0V
Volr
Ireset=10mA, Vsa=0.0V
Ireset Volr=1.0V, Vsa=0.0V
Ict Vsb=5.0V, Vct=0.5V
Iihc Vsc=5.0V
Iilc Vsc=0.0V
Vsc
Top=-40°C to +85°C
ΔVsc Vcc=3.5V to 6.0V
Iohc Vohc=5.0V
Volc Ioutc=4mA, Vsc=5.0V
Ioutc Volc=1.0V, Vsc=5.0V

Min.
Typ.
1.2
5.0
65
75
4.10
4.20(4.05)* 4.20
4.20
4.30
(4.15)* 4.30
50100
1.162 1.180(1.152)* 1.180
31530
0-0.250
4.50
4.90
0.28
0.38
2060
9120-0.50
1.192 1.210(1.181)* 1.210
300.15615

Max.
18.0(130)(150)
4.30(4.35)*
4.40(4.45)*
150
1.198(1.208)*
1045
0.25
0.40
0.50

Unit
VμA
VVmVVmV
mV
μA
VmA
μA

160.5μA
1.228
V(1.239)*
10mV
1.0μA
0.40
VmA

RESET signal holding minimum
supply voltage

Vccl Volr=0.4V, Ireset=200μA

-

0.8

1.2

VVsa, Vsb input pulse width
Reset hold time

tpi
tpo
trtf
tpd
tphl
tplh

5.0
0.5-

1.0
1.0
0.1
2
0.5
1.0

1.5
1.5
0.5
10-us
msus
ususususRESET rise timeRESET fall time
Propagation delay time

Ct=0.01μF
Rl=2.2kΩ, Cl=100pF
VSB pin
VSC pin, Rl=2.2kΩ, Cl=100pF* The values enclosed in parentheses ( ) are setting assurance values.
* Ct range is 0.001 μF to 10 μF.
* The voltage range is 10% to 90% at testing the reset output transition time.

Rev.2.24 / 12

ELM7C377142xA CMOS voltage detector, 2 channels, 18V operation, reset hold by ext.C
http://www.elm-tech.com■Timing chart
Fig.1: Basic operation■Function Explanation(1) When Vcc rises to about 0.8 V, RESET goes Low.
(2) When Vcc reaches Vs +Vhys, Ct then begins charging. RESET remains low during this time.
(3) RESET goes high after a certain period Tpo.
Tpo ≈ Ct × 105 (Refer to “Reset hold time(tpo) vs. Ct pin capacitance” in “■Typical characteristic curves.”)(4) When Vcc level drops lower then Vs, then RESET goes low and Ct starts discharging.
(5) When Vcc level reaches Vs + Vhys, then Ct starts charging.In the case of voltage sagging, if the period fromthe time Vcc goes lower than or equal to Vs to the time Vcc reaches Vs +Vhys again, is longer than tpi, Ct isdischarged and charged successively.
(6) After Tpo passes, and Vcc level exceeds Vs + Vhys, then RESET goes high.
(7) When Vcc becomes less than Vs, (4) to (6) is repeated.
(8) If Vcc drops to 0V, RESET keeps “Low” until Vcc reaches 0.8V.

■Marking
SOP-8

SON8-3×3

SymbolaMark0 to 9Content
Last numeral of A.D.

bc

A to M (excepted I.)
0 to 9Assembly monthLot No.
Rev.2.2

5 / 12

ELM7C377142xA CMOS voltage detector, 2 channels, 18V operation, reset hold by ext.C
http://www.elm-tech.com■Application circuit example
1) 5V Power Supply Monitor
Monitored by Vsa. Detection threshold voltage is Vsal and Vsah.

2) 5V Power Supply Voltage Monitor (Externally Fine-Tuned Type)The Vsa detection voltage can be adjusted externally.
Resistance R1 and R2 are set sufficiently lower than the IC internal partial voltage resistance, so that the detection voltage can be set using the ratio between resistance R1 and R2. (Refer to the table below).
* R1, R2 calculation formula (when R1 << 100 kΩ, R2 <<40 kΩ)
Vsal≈(R1+R2 )×1.18/R2[V], Vsah≈(R1+R2)×1.21/R2[V]R1(kΩ)
10.00

R2(kΩ)
3.90

Detection voltage : Vsal(V)
4.21

Detection voltage : Vsah(V)
4.31

9.10

3.90

3.93

4.033) Arbitrary Voltage Supply Monitor-1 (Vcc≤5.5V)* Detection Voltage can be set by R1 and R2. Detection Voltage = (R1 + R2) × 1.18/R2* Connect Pin7 to Vcc when Vcc less than 4.45V.
* Pin7 can be opened when Vcc greater than 4.45V. Power dissipation can be reduced. Consumption current
decreases when pin7 is open.
Note: Hysteresis of 30mV at Vsb at termination is available. Hysteresis width dose not depend on (R1+R2).

Rev.2.2
6 / 12

ELM7C377142xA CMOS voltage detector, 2 channels, 18V operation, reset hold by ext.C
http://www.elm-tech.com

4) Arbitrary Voltage Supply Monitor-2 (Vcc>5.5V)

ELM7C377142xA* Detection Voltage can be set by R1 and R2. Detection Voltage=(R1 + R2) × 1.18/R2* The RESET signal output is ≈ 0V(low level) and ≈ 5V(high level). Vcc voltage cannot be output. Do not pullup RESET to Vcc.
* Changing the resistance ratio between R4 and R5 changes the constant voltage output, thereby changing thevoltage of the high level RESET output. Note that the constant voltage output should not exceed 5.5V.
* The 5V output can be used as a power supply for control circuits with low current consumption.
* As an example of R3 value, R3 = (Vcc-5) /0.01 for 10mA output.

5) 5V and 12V Power supply monitor (2 types of power supply monitor Vcc1=5V, Vcc2 =12V)* 5V is monitored by Vsa. Detection voltage is about 4.2V.
* 12V is monitored by Vsb. When R1=390kΩ and R2=62kΩ, detection voltage is about 8.6V. Generally thedetection voltage is determined by the following equation.
Detection Voltage=(R1+R2)×1.18/R2

ELM7C377142xA

Rev.2.2
7 / 12

ELM7C377142xA CMOS voltage detector, 2 channels, 18V operation, reset hold by ext.C
http://www.elm-tech.com

6) 5V Power supply monitor with forced RESET input (Vcc=5V)
RESIN is an TTL compatible input.

ELM7C377142xA

7) 1.210V Reference voltage generation and 5V monitoringResistor R1 determines Reference current. Using 1.2 kΩ as R1, reference current is about 2 mA.

8) 5V Power supply monitor with non-inverted RESETIn this case, Comparator C is used to invert RESET signal. OUTC is an open-drain output. RL is used as apull-up resistor. Here, please be careful that the input voltage of the VSB pin does not exceed the maximum absolute ratings. It is recommended that the input voltage at the VSB pin be less or equal than 6.5V.

LRev.2.2
8 / 12

ELM7C377142xA CMOS voltage detector, 2 channels, 18V operation, reset hold by ext.C
http://www.elm-tech.com

9) Supply voltage monitoring with delayed trigger
When the voltage shown in the diagram below is applied at Vcc, the minimum value of the input pulse width
is increased to approximately 75µs (when C1=1000pF). The formula for calculating the minimum value of theinput pulse width [Tpi] is : Tpi[µs]≈7.5×10-2×C1[pF]
Here, please be careful that the input voltage of the VSB pin does not exceed the maximum absolute ratings.
It is recommended that the input voltage at the VSB pin be less or equal than 6.5V.

■Reference land pattern
SOP-8 208mil

7.45mm

1.27mm

0.60mm

1.75mm

SOP-8 150mil

Rev.2.2
9 / 12ELM7C377142xA CMOS voltage detector, 2 channels, 18V operation, reset hold by ext.C
http://www.elm-tech.com■Typical characteristic curves
18250

Power supply current Icc1(mA)

Power supply current Icc1(�A)

300Power supply current (Icc1) vs.
Power supply voltage-1200150Top=+85°C

100

Top=+25°C

50
Top=-40°C

02.0

3.0

4.0

5.0

64
Top=-40°C

218

Top=+85°C

Top=+25°C

50
Top=-40°C

1.0

510

1520

2.0

3.0

4.0

5.0

6.0

16

Top=+85°C

1412

Top=+25°C

1864
2

Top=-40°C

50101520

Power supply voltage Vcc(V)Power supply voltage Vcc(V)Output voltage (RESET) vs.
Power supply voltage

Detection voltage(Vsc) vs.
Operating ambient temperature

1.26

4Detection voltage Vsc(V)Output voltage Vreset(V)

8Power supply current (Icc2) vs.
Power supply voltage-2

100

3

1

Top=+25°C

1

Power supply current (Icc2) vs.
Power supply voltage-1

1502

12

Power supply voltage Vcc(V)200

5Top=+85°C

14Power supply voltage Vcc(V)

250

0160

6.0

Power supply current Icc2(mA)

Power supply current Icc2(�A)

300

1.0

Power supply current (Icc1) vs.
Power supply voltage-2

Top=+85°C
Top=+25°C

1.21

Top=-40°C

01234
Power supply voltage Vcc(V)

1.16-50

5-250+25+50+75+100

Operating ambient temperature Top(°C)

Rev.2.2
10 / 12

ELM7C377142xA CMOS voltage detector, 2 channels, 18V operation, reset hold by ext.C
http://www.elm-tech.com
Detection voltage(Vsb) vs.
Operating ambient temperature

4.5
Detection voltage Vsah, Vsal (V)Detection voltage Vsbh, Vsbl (V)

1.25

Vsbh

1.20

Vsbl

1.15-50-25

0+25+50+75

Detection voltage(Vsa) vs.
Operating ambient temperature

4.4
Vsah

4.3
Vsal

4.2
4.1
4.0-50+100

Detection voltage(Vsb,Vsc) vs.
Power supply voltage

Vsbh

1.20

VscVsbl1.15051015+7502051015

Output voltage(Vohr) vs. Output current

5.0

10-1
10-2

Top=+25°C-31010-410-520

Power supply voltage Vcc(V)

Top=-40°C

1+100

Top=+85°C

0.5

Output voltage Vohr(V)Reset hold time tpo(s)+50Top=+25°C

Reset hold time(tpo) vs. Ct pin capacitance

10+25

Top=-40°C

1.0Power supply voltage Vcc(V)1020

Reset hold time(tpo) vs. Power supply voltage(Ct=0.01�F)
1.5

Reset hold time tpo(ms)Detection voltage Vsc, Vbl, Vbh (V)1.25-25

Operating ambient temperature Top(°C)

Operating ambient temperature Top(°C)

Top=+85°C

4.5

Top=+25°C

Top=+85°C
Top=-40°C

10-64.010-12 10-11 10-10 10-9 10-8 10-7 10-6 10-5 10-4Ct pin capacitance Ct(F)0510
Output current Ireset(�A)

15

Rev.2.2
11 / 12

ELM7C377142xA CMOS voltage detector, 2 channels, 18V operation, reset hold by ext.C
http://www.elm-tech.com

Output voltage(Volc) vs. Output sink current
2.0

Output voltage Vo�c(V)Output voltage Vo�r(V)Output voltage(Volr) vs. Output sink current
2.0

Top=+85°C

1.0

Top=+25°C

1.010203040Output sink current Ireset(�A)Top=+25°C

0.5
Top=-40°C

Top=-40°C

0Top=+85°C

1.505051015Output sink current Ioutc(�A)

20

Rev.2.2
12 / 12