M54124L Datasheet, PDF (1/6 Pages) Mitsubishi Electric Semiconductor – EARTH LEAKAGE CURRENT DETECTOR

MITSUBISHI <CONTROL / DRIVER IC>
M54124L
EARTH LEAKAGE CURRENT DETECTOR
DESCRIPTION
The M54124L is a semiconductor integrated circuit consisting of an
amplifier for a high-speed earth-leakage circuit breaker.
FEATURES
q Satisfies JIS C 8371
q Temperature-stable input current threshold
q High-input sensitivity (VT = 6.5mV)
q Low external component count
q Highly resistant to noise and power surges
q Low power dissipation (Pd = 5mW typ)
q Can be used at 100V and 200V
q High-density mounting eight-pin SIL package
q Wide operating temperature range (Ta = -20 – +80°C)
APPLICATION
High-speed earth-leakage circuit breakers
FUNCTION
The M54124L 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 and voltage
regulator. It is connected to the secondary side of the zero-current
transformer, ZCT, and detects leakage current in both inputs of the
differential amplifier. Signals amplified by the differential amplifier
are integrated by an external capacitor, and applied to the input pin
of a one-shot multivibrator circuit having time-delay characteristics
that are suitable for high-speed earth-leakage circuit breakers
(such as specified in JIS C 8371). The one-shot multivibrator circuit
normally maintains a low output. When the input current (earth-
leakage) exceeds a specified level, a one-shot high pulse is output
to turn on an externally connected thyristor.
PIN CONFIGURATION (TOP VIEW)
Reference voltage
Input
VR ← 1
IN → 2
GND 3
Differential amplifier output OD ← 4
One shot multivibrator A MA → 5
One shot multivibrator B MB →← 6
Output OS ← 7
VS
8
Outline 8P5
BLOCK DIAGRAM
VR
1
0
Comparator
VCC
Output
circuit
VR
1
One shot
multivibrator
A
0
1
One shot
multivibrator
B
0
1
2
3
45
6
7
8
VR
IN
GND
OD MA
MB
OS
VS
Reference Input
Differential One shot
One shot
Output
voltage
amplifier multivibrator A
multivibrator B
output