UNISONIC TECHNOLOGIES CO.

, LTD
M54123L LINEAR INTEGRATED CIRCUIT

EARTH LEAKAGE CURRENT

DETECTOR

„ DESCRIPTION
The UTC M54123L is a semiconductor integrated circuit with
amplifier for a high-speed earth leakage circuit breaker.
For the amplifying parts of earth leakage circuit breaker, the
UTC M54123L consists of differential amplifier, latch circuit and
voltage regulator.
In normal operating, the UTC M54123L should be connected to
the secondary side of the ZCT (zero current transformers). Here
the ZCT detects leakage current different amplifiers’ both input.
Then the signals which have been amplified are integrated by
an external capacitor. The integrated signal connects to the input
terminal of latch circuit whose output is suitable for the
characteristics of high- speed earth leakage circuit breaker.
Until the input voltage reaches the fixed level, latch circuit
doesn’t become high. Then drives a thyristor which is connected to
latch circuit’s output terminal. Once the trigger latch circuit, only the
power on again to reset.

„ FEATURES
* With good input sensitivity current temperature characteristics
* High input sensitivity :VT=6.1mV (Typ.)
* Only need low external component count
* High noise and surge-proof
* Low power dissipation :PD=5mW (Typ.)
* May be used both as 100V and 200V.
* Wide temperature range : from -20 °C to +80°C

„ ORDERING INFORMATION
Order Number
Package Packing
Lead Free Halogen Free
M54123LK-D08-T M54123LG-D08-T DIP-8 Tube
M54123LK-G08-T M54123LG-G08-T SIP-8 Tube
M54123LK-S08-R M54123LG-S08-R SOP-8 Tape Reel

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M54123L LINEAR INTEGRATED CIRCUIT

„ MARKING
DIP-8 SIP-8 SOP-8

„ PIN CONFIGURATIONS

„ PIN DESCRIPTION
PIN NO. PIN NAME DESCRIPTION
1 VR Reference voltage terminal
2 IN Input terminal
3 GND Ground
4 OD Differential amplifier output terminal
5 SC Latch input terminal
6 NR Terminal for noise absorption
7 OS Output terminal
8 VS Supply voltage terminal

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M54123L LINEAR INTEGRATED CIRCUIT

„ BLOCK DIAGRAM

Reference Voltage Generator

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M54123L LINEAR INTEGRATED CIRCUIT

„ ABSOLUTE MAXIMUM RATING (unless otherwise specified)

PARAMETER SYMBOL RATINGS UNIT
Supply Current IS 8 mA
Between VR-IN (Note 2) 250 mA
VR Pin Current Between VR-GND IVR 30 mA
Between IN-VR(Note 2) -250 mA
Between IN-VR(Note 2) 250 mA
IN Terminal Current Between IN-GND IIN 30 mA
Between VR-IN (Note 2) -250 mA
SC Terminal Current ISC 5 mA
Power Dissipation PD 200 mW
Operating Temperature TOPR -20~ +80 °C
Storage Temperature TSTG -55~ +125 °C
Notes: 1. Absolute maximum ratings are those values beyond which the device could be permanently damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not implied.
2. Current value between VR and IN, and between IN and VR is less than 1ms in the pulse width, and duty
cycle is less than 12%, In applying AC current continuously, it is 100 mA in the off-state.
„ RECOMMENDED OPERATING CONDITIONS (unless otherwise specified)
PARAMETER SYMBOL MIN TYP MAX UNIT
Supply Voltage When Latch Circuit Is Off-State VS 12 V
External Capacitor Between Vs and GND CVS 1 μF
External Capacitor Between Os and GND COS 1 μF
„ ELECTRICAL CHARACTERISTICS (TA=-20~+80°C, unless otherwise specified)
PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNIT
TA=-20°C 580 μA
VS=12V,VR-VI=30mV
Supply Current IS1 TA=25°C 400 530 μA
(See Test Circuit 1)
TA=80°C 480 μA
VS=16V, VR-VI, TA=-20~+80°C
Trip Voltage VT 4 6.1 9 mVrms
(Note2) (See Test Circuit 2)
VS=16V, VR-VI=30mV, VOD=1.2V, TA=25°C
Timed Current1 ITD1 -12 -30 μA
(See Test Circuit 3)
VS=16V, short circuit between VR and VI,
Timed Current2 ITD2 17 37 μA
VOD=0.8V, TA=25°C (See Test Circuit 4)
IS1=580μA,TA=-20°C -200 μA
VSC=1.4V,VOS=0.8V
Output Current IO IS1=530μA,TA =25°C -100 μA
(See Test Circuit 5)
IS1=480μA,TA =80°C -75 μA
SC “ON” Voltage (Note3) VSC(ON) VS=16V, TA=25°C (See Test Circuit 6) 0.7 1.4 V
SC Input Current ISC(ON) VS=12V, TA=25°C (See Test Circuit 7) 5 μA
VS=12V,VOSL=0.2V, TA=-20~+80°C
Output Low-Level Current IOSL 200 μA
(See Test Circuit 8)
VS=12V, IIC=20mA, TA=-20~+80°C
Input Clamp Voltage VIC 4.3 6.7 V
(See Test Circuit 9)
Differential Input Clamp IIDC=100mA, TA=-20~+80°C
VIDC 0.4 2 V
Voltage (See Test Circuit 10)
Maximum Current Voltage VSM ISM=7mA, TA=25°C (See Test Circuit 11) 20 28 V
VR-VI, VOS=0.6V, TA=-20~+80°C
Supply Current 2(Note 4) IS2 1100 μA
(Note 5) (See Test Circuit 12)
Latch Circuit is Off-State
VS(OFF) TA=25°C (See Test Circuit 13) 0.5 V
Supply Voltage (Note6)
VS=16V,VR-VI=0.3V, TA=25°C
Operating Time (Note 7) TON 2 4 ms
(See Test Circuit 14)

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M54123L LINEAR INTEGRATED CIRCUIT
„ ELECTRICAL CHARACTERISTICS (Cont.)
Notes: 1. Typical values are at TA=25°C
2. When standard value of voltage (60Hz) between VR and VI is minimum, and output OS is low-level, or
when standard value of voltage (60Hz) between VR and VI is maximum, and output OS is high-level, it is
considered as a good one.
3. When standard value of voltage VSC(ON) is minimum, and output OS is low-level, or when standard value of
voltage VSC(ON) is maximum, and output OS is high-level, it is considered as a good one.
4. Supply current 2 is necessary to keep high in output OS.
5. After applying 30mV between VR and VI and shorting between them, it is considered as a good one if
standard value of IGT flows out of output OS.
6. After supply voltage applies 12V and output OS is high-level, it is considered as a good one in the
standard value of supply voltage and in the low-level of output OS.
7. Operating time is a time from applying fixed input till operating latch circuit in 0.047μF between OD and
GND.

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M54123L LINEAR INTEGRATED CIRCUIT

„ TEST CIRCUITS

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M54123L LINEAR INTEGRATED CIRCUIT
„ TYPICAL APPLICATION CIRCUIT

High-Speed Leakage Circuit Breaker With UTC M54123L

Note: The value of R1, R2, C4, and C5 should be chosen in order to keep at least 12V in Vs.
Please connect C4 (>1μF) and C2 (<1μF).
ZCT and load resistance RL of ZCT are connected between input pin 1 and 2.
Protective resistance (RP=100Ω) must be insurted.
RL and amplifier’s output (in Pin 4) regulates sensitivity current
External capacitor C1 between pin 4 and GND is used for noise removal.
Please connect a varistor or a diode (2 pcs.) to ZCT in parallel, because of when large current is grounded in
the primary side (AC line) of ZCT, the following situation can be abandoned: The wave form in the secondary
side of ZCT is distorted and some signals do not appear in the output of amplifier.
Please connect capacitor (about 0.047μF) between pin 6 and pin 7.
Capacitor C6 between pin 1 and GND is about 0.047μF for removing noise.

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M54123L LINEAR INTEGRATED CIRCUIT

„ TYPICAL CHARACTERISTICS

Vcc Voltage vs. Supply Voltage Supply Current 1 vs. Supply Voltage
12 700

Ta=-25°C
10 600

Supply Current 1, Is1 (µA)

25°C
Vcc Voltage, VCC (V)

8 500
75°C
Ta=-25°C
6 400
25°C

4 300
75°C
2 200

0 100
8 10 12 14 16 18 20 0 5 10 15 20 25 30
Supply Voltage, Vs (V) Supply Voltage, Vs (V)
Vcc voltage generates by the constant voltage circuit in IC.
This is measured not by M54123L but by a special
element.

Reference Voltage vs. Supply Voltage Bias Current vs.Ambient Temperature

2.5 1000
Ta=75°C
900
2.0 800
Reference Voltage, VR (V)

25°C
Bias Current, IIN (nA)

700
-25°C
1.5 600
500
1.0 400
300

0.5 200
100
0 0
0 4 8 12 16 20 -40 -20 0 20 40 60 80 100
Supply Voltage, Vs (V) Ambient Temperature, Ta (°C)

Differential Amplifier Output Voltage

vs.Differential Input Voltage Timing Current vs.Ambient Temperature
2.5 -50
Differential Amplifier Output Voltage, VOD

2.0 -40
Timed Current 1, ITD1 (µA)

1.5 -30
(V)

1.0 -20
Ta=75°C

0.5 -25°C -10

25°C

0 0
5 6 7 8 9 10 -40 -20 0 20 40 60 80 100
Differential Input Voltage △VI=VR-VIN (mV) Ambient Temperature, Ta (°C)

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M54123L LINEAR INTEGRATED CIRCUIT

„ TYPICAL CHARACTERISTICS(Cont.)

UTC assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other
parameters) listed in products specifications of any and all UTC products described or contained herein.
UTC products are not designed for use in life support appliances, devices or systems where malfunction
of these products can be reasonably expected to result in personal injury. Reproduction in whole or in
part is prohibited without the prior written consent of the copyright owner. UTC reserves the right to
make changes to information published in this document, including without limitation specifications and
product descriptions, at any time and without notice. This document supersedes and replaces all
information supplied prior to the publication hereof.

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