EARTH LEAKAGE CURRENT DETECTOR
M54125L/P
MITSUBISHI <CONTROL / DRIVER IC>
DESCRIPTION
The M54125 is a semiconductor integrated circuit consisting of an
amplifier for high-speed earth leakage circuit breaker.
FEATURES
●Satisfies JIS C 8371
●Temperature-stable input current trigger threshold (VLKT = 9mV)
●Capable of detecting a lost phase on the neutral line
●Economical, low external component count
●Highly resistant to noise and power surges
●Wide operating temperature range (Ta = -20 – +80°C)
APPLICATION
High-speed earth-leakage circuit breakers
FUNCTION
The M54125 is a semiconductor integrated circuit for use in the
amplifier section of earth-leakage circuit breakers. It consists of a
differential amplifier, one-shot circuit, output circuit, current
regulator, waveform regulator and delay circuit. The following
description refers to the block diagram, application example, and
operational waveforms.
PIN CONFIGURATION
(
TOP VIEW
)
BLOCK DIAGRAM (Note: Pin No. in parentheses are of M54125L)
Outline 14P5A
Outline 10P2-C
Input
Bias voltage
Capacitor
Output
ILK
VB
MM
OUT
GND
VS
RX
IBL
WF
TD
External resistor
Input
Capacitor CWF
Capacitor CTD
10
7
8
9
1
4
3
2
65
M54125P
←
→
→
←
→←
→←
←
←
1
4
5
3
2
6
7
8
9
10
12
13
14
11
M54125L
MM
OUT
GND
NC
TD
NC
NC
VS
ILK
VB
NC
→
←
Capacitor
Output
Capacitor CTD
Bias volta
g
e
Input
WF
IBL
RX
→←
→
→
→←
→←
Capacitor CWF
Input
External resistor
N.C: no connection
VCC
VS
Voltage
regulator
VBA • VLKT
VBLT
RX IBL WF TD
External
resistor Input Capacitor CWF Capacitor CWF
Bias
current
source Comparator
Comparator
Amplifier
ILK VB MM OUT GND
Input Bias Capacitor Output
Wave-
form
regulator
Delay
circuit
Output
circuit
One-shot
multi vibrator
M54125L/P
A
1 2 3 45
678910(12) (9) (8) (7)
(
2
)
(
3
)
(
1
)
(
14
)
(
13
)
(5)
EARTH LEAKAGE CURRENT DETECTOR
M54125L/P
MITSUBISHI <CONTROL / DRIVER IC>
ABSOLUTE MAXIMUM RATINGS
(
Ta = -20 – 80°C unless otherwise noted
)
Supply voltage
OUT applied voltage
Supply surge current
ILK input voltage
IS
Symbol Ratings Unit
Parameter Conditions
IS(SO)
VOUT
0– 12
-0.3 – 6
mA
mA
PdPower dissipation
Topr Operating temperature
Tstg Storage temperature
-0.3 – 4
160 mW
(Note 1)
Pin VB serves as the voltage
reference
When external voltage is applied
0– 6
-1.8 – +1.8
-20 – 80
-55 – 125
V
°C
°C
V
Note 1: IS(SG) current waveform, which is given in the following diagram, shall be one shot or less per minute.
V
RECOMMENDED OPERATING CONDITIONS
(
Ta = -20 – 80°C unless otherwise noted
)
Limits
Min. Typ. Max.
Symbol Unit
VSSupply voltage 12
Supply current 5.6
IS
CMM External capacitor MM
mA
µF
Average supply current frequency
per cycle
∆VILK
VIBL IBL input voltage V
CWF
CTD
RX
External capacitor WF
External capacitor TD
External resistor RX
Average power supply current per
cycle
When output OUT is OFF
0.22
1
6.8
27
µF
µF
kΩ
Parameter
Handling of unused pins when the abnormal voltage detection function is not used
• Pin RXmust be left open
• Pin TD must be shorted to GND
• Pin WF and pin IBL may be left open or shorted to GND
IS(SG)
1
µ
S40
µ
S
12mA
6mA
0mA
EARTH LEAKAGE CURRENT DETECTOR
M54125L/P
MITSUBISHI <CONTROL / DRIVER IC>
ABNORMAL VOLTAGE DETECTION FUNCTION
Normally VIBL, fixed amplitude AC supply that has been rectified
and divided by a resistor, is input to abnormal voltage input IBL.
When a fault occurs in the neutral line N, successive peaks of VIBL
become alternately small and large, with the levels determined by
the load on the AC power lines A and B.
When the amplitude of VIBL exceeds the abnormal voltage trip
voltage VBLT, capacitor CWF connected to pin WF discharges. After
the discharge shase is completed, charging begins again.) When
voltage VWF at WF drops below the WF threshold voltage,
capacitor CTD at TD charges, and after delay time tTD, when
voltage VTD at TD reaches the TD threshold voltage, output OUT
turns on, activating the circuit breaker. To avoid misoperation due
to the effect of repeated one-shot noise that brings VIBL above
VBLT, the voltage drops to the initial value only after time tWF.
This abnormal voltage detection circuit is enabled only when an
external resistor RXis connected to pin RXto enable the current
flow.
LEAKAGE DETECTION FUNCTION
When leakage current current Ig appears on the primary side of
zero-current transformer, ZCT, leakage signal voltage V ILK appears
on the secondary side and is input at ILK with bias VB as the
reference. In the half cycle when VILK is negative, capacitor CMM
connected to MM charges until VILK reaches the DC trip voltage.
If the voltage at MM does not reach the MM positive threshold
voltage, when the charging phase is completed, capacitor CMM
discharges at a small current. The output OUT is reset to the off
state (in which output current flows in) when VMM descends to the
MM negative threshold voltage.
Earth-leakage currents are detected when the amplitude of input
voltage VILK exceeds the DC trip voltage VLKT for longer than the
detection time tMM. The output OUT turns on for time tOUT. The
output current is used to turn on the thyristor that opens the
breaker contacts.
WAVEFORM DIAGRAM
1) Voltage waveform when earth leakage is detected.
MM positive direction threshold voltage Note: Values in the parentheses are for reference onl
y
.
MM negative direction threshold voltage
2) Voltage waveform when abnormal voltage is detected.
WF threshold voltage
TD threshold voltage
VILK
VMM
VLKT
IMM
(
3ms
)
tOU
T
(45ms)
VBT
L
(3.9V)
Nois
e
VISL
VWF
tW
F
(55ms) VTD
tTD(300ms)
VB
0
0
0
0
0
0
ILK
VB
MM
OUT
IBL
WF
TD
OUT
EARTH LEAKAGE CURRENT DETECTOR
M54125L/P
MITSUBISHI <CONTROL / DRIVER IC>
25
25
-20
25
80
25
25
25
25
25
25
ELECTRICAL CHARACTERISTICS
(
VCC = 5V and Ta = -20 – 80°C unless otherwise noted
)
Limits
Min. Max.
Symbol Test conditions Unit
Parameter
IS2 Supply current 2 mA
µA
ms
VS= 12V, ∆VILK = 0mV, Out : “OFF” 1.2
370
mA
mVrms
µA
IMM+
IMM-
tMM
tOUT
VSM
IS3
ITD+
IS4
tDT
VBLT
IIBL
IWF+
tWF
Temperature
Pin VS
V
mA
mA
mA
V
µA
ms
Test
circuit
VS= 16V, ∆VILK = -15mV, Out : “ON”
VS= 16V, VLKT : 60Hz
Test circuit 3
VS= 16V, ∆VILK = 0mV, VMM = 0.8V
VS= 16V, ∆VILK = -15mV, VMM = 0.8V
VS= 16V
VS= 16V, ∆VILK = 0mV, VOUT = 0.2V
VS= 16V, ∆VILK = -15mV
VOUT = 0.8V
Pin VS
Pin ILK
and VB
Pin MM
Pin MM
Pin MM
Pin OUT
Pin OUT
Pin OUT
Pin VS
Pin VS
Pin VS
Pin IBL
Pin IBL
Pin WF
Pin WF
Pin WF
Pin TD
Pin TD
Pin TD
VS= 16V
IS= 3.5mA
VS= 12V, VILK : 0mV
VIBL = 0V, OUT : “OFF”
Test circuit 2
VS= 12V, VILK : -15mV
VIBL = 12V, OUT : “ON”
Test circuit 2
VS= 16V
VS= 16V, VIBL = 4.5V
Test circuit 7
VS= 16V, VIBL = 4.5V, VWF = 0.5V
VS= 16V, VIBL = 0V, VWF = 0.5V
VS= 16V
VS= 16V, VIBL = 0V, VTD = 0.5V
VS= 16V, VIBL = 4.5V, VTD = 0.5V
VS= 16V
IS1
VLKT
IOU+
IOU-
IWF-
ITD-
Supply current 1
Trip voltage
Sink current
Source current
Detect inhibit time
Sink current
Source current
Output pulse width
Maximum current
voltage
Supply current 3
Supply current 4
Trip voltage
Input current
Sink current
Source current
Recovery time
Sink current
Source current
Delay time
4
170
-110
1.7
150
-200
-100
-70
25
20
3.6
1
-22
35
1
-22
200 -30
420
-30
70
4.1
0.8
1
1.4
26
100
0.7
9
-250
4µA
µA
ms
µA
mA
µA
ms
1
4
10
1
4
6
8
7
11
5
5
10
8
9
9
12
APPLICATION EXAMPLE
VCC
VS
Voltage
regulator
VBA • VLKT
VBLT
RX
IBL WF TD
Bias
current
source Comparator
Comparator
Amplifier
ILK VB MM OUT GND
Delay
circuit
Output
circuit
Waveform
regulator
One-shot
multivibrator
RX
CWF CTD
CMM
ZCT
ANB
ANB
Load
AC power input
M54125L/P
A
Note 2
MZ Core Series by Soryo Denshi Kagaku Co., Ltd (Mitsubishi Subsidiary)
Tel. +81-427-74-7813
Note 2 :
EARTH LEAKAGE CURRENT DETECTOR
M54125L/P
MITSUBISHI <CONTROL / DRIVER IC>
TEST CIRCUIT
(
CMM = 0.22
µ
F, CTD = 6.8
µ
F and RX= 27kΩ unless otherwise noted
)
1IS 1 and IS 2 Measurement 2IS 3 and IS 4 Measurement
3VLKT 4IMM+ and IMM- Measurement
5IOU+, IOU- Measurement 6VSM Measurement
∗: IS 2 is the value after OUT turns on. (Vout > 0.5V) ∗: IS 4 is the value after OUT turns on.
∗:VLKT is the value of VIBL when OUT turns on as VIBL is
gradually increased.
∆VILK
VOUT
IS 1, IS 2
VS
A
CMM
MD234 or
E
q
uivalent
ILK
VB
MM
OUT
GND
VS
RX
IBL
WF
TD
VIBL
VOUT
VS
CMM
ILK
VB
MM
OUT
GND
VS
RX
IBL
WF
TD
VOUT
IS 3, IS 4
VS
A
CMM
ILK
VB
MM
OUT
GND
VS
RX
IBL
WF
TD CTD
CWF
RX
VIBL
∆VILK
VMM
VS
AIM
M
+
ILK
VB
MM
OUT
GND
VS
RX
IBL
WF
TD
IM
M
-
∆VILK
V
ILK
VB
MM
OUT
GND
VS
RX
IBL
WF
TD
VSM
IS
+
-
VOUT
VS
A
CMM
ILK
VB
MM
OUT
GND
VS
RX
IBL
WF
TD
IOU-
∆VILK
IOU+
EARTH LEAKAGE CURRENT DETECTOR
M54125L/P
MITSUBISHI <CONTROL / DRIVER IC>
7VBLT,IIBL Measurement 8IWF+, IWF- Measurement
9ITD+, ITD- Measurement 10 tMM,tOUT Measurement
11 tWF Measurement 12 tTD Measurement
∗: VBLT is the value of VIBL when VF = 0.5V.
VS
A
ILK
VB
MM
OUT
GND
VS
RX
IBL
WF
TD VVIBL
VWF
+
-
IIBL
RX
VS
ILK
VB
MM
OUT
GND
VS
RX
IBL
WF
TD
CMM
VILK
VOUT
VILK
VOUT
1.8V
0.5V
1.4V
tOUT
tMM
10ms
VS
ILK
VB
MM
OUT
GND
VS
RX
IBL
WF
TD CTD
VOUT
RX
C
µ
FVIBL
0.5V
4.5V
0V
VOUT
VIBL
tTD
VS
ILK
VB
MM
OUT
GND
VS
RX
IBL
WF
TD
RX
C
µ
F0.5V
3kΩVTD
VIBL
0.5V
4.5V 0V
VTD
VIBL
tWF
VS
ILK
VB
MM
OUT
GND
VS
RX
IBL
WF
TD A
VIBL
RX
VTD
ITD+
ITD-
VS
A
ILK
VB
MM
OUT
GND
VS
RX
IBL
WF
TD VWF
RX
VIBL
IWF+
IWF-
