M51957A,B/M51958A,B
Voltage Detecting, System Resetting IC Series
REJ03D0778-0300
Rev.3.00
Sep 18, 2007
Description
M51957A,B/M51958A,B are semiconductor integrated circuits for resetting of all types of logic circuits such as CPUs,
and has the feature of setting the detection voltage by adding external resistance.
They include a built-in delay circuit to provide the desired retardation time simply by adding an external capacitor.
They fined extensive applications, including battery checking circuit, level detecting circuit and waveform shaping
circuit.
Features
• Few external parts
• Large delay time with a capacitor of small capacitance (td ≈ 100 ms, at 0.33 µF) (M51957, M51958)
• Low threshold operating voltage (Supply voltage to keep low-state at low supply voltage):
0.6 V (Typ) at RL = 22 kΩ
• Wide supply voltage range: 2 V to 17 V
• Wide application range
Application
• Reset circuit of Pch, Nch, CMOS, microcomputer, CPU and MCU, Reset of logic circuit, Battery check circuit,
switching circuit back-up voltage, level detecting circuit, waveform shaping circuit, delay waveform generating
circuit, DC/DC converter, over voltage protection circuit
Recommended Operating Condition
• Supply voltage range: 2 V to 17 V
Pin Arrangement
M51957AL/BL
M51958AL/BL
M51957AFP/BFP
M51958AFP/BFP
5 Output
4 Delay capacitor
3 GND
2 Input
1 Power-supply
(Top view)
Outline: 5P5T
NC 1
8 NC
Input 2
7 Power-supply
NC 3
6 Output
GND 4
5 Delay capacitor
(Top view)
NC: No Connection
Outline: PRSP0008DE-C (recommend)
PRSP0008DA-A (8P2S-A) (not recommend for new design)
REJ03D0778-0300 Rev.3.00 Sep 18, 2007
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