MITSMI MM1478D, MM1478A, MM1478M, MM1478F Datasheet

MITSUMI

Regulator+Reset IC MM1478

Regulator+Reset IC

Monolithic IC MM1478

Outline

This IC, developed for use in CD-ROM drives, combines a 3V regulator adapted to low power consumption
with a much-sought reset function (regulator input monitoring), with internal delay circuit, set to detect 4.2V.

Features

1. Large output current 300mA max.

2. High ripple rejection rate 80dB typ.

3. Internal thermal shutdown circuit.

4. Internal current-limiting circuit.

5. Adjustment-free reset detection voltage 4.2V typ.

6. Easy to set delay time from voltage detection to reset release.

Package

SOP-8D

Applications

Pin Assignment

CD-ROM drive.

1423

7685

SOP-8D

(TOP VIEW)

MITSUMI

1 N. C
2 RESET

---------------------------------------------------------------------

3 CONT
4 V

IN

5 VOUT
6 N. C
7 GND
8 Cd

Rank table

Rnak Regulator output voltage (V) Detection voltage (V)

A 3.40±0.05 4.20±0.09
D 3.30±0.05 4.20±0.09
F 3.30±0.05 3.90±0.09

M 2.50±0.05 4.20±0.09

MITSUMI

Regulator+Reset IC MM1478

Pin Description

MITSUMI

Pin No.

Pin name

Functions Equivalent circuit diagram

1 N. C

2 RESET

---------------------------------------------------------------------

Input voltage detection output

Input voltage detection output pin

RESET

---------------------------------------------------------------------

pin logic

3 CONT Output voltage on/off-control pin

4 V

IN Voltage supply input pin

5 V

OUT Regulator Output pin

6 N. C

7 GND GND pin

8 Cd Delay time capacitor pin

t

PLH=100000·C

t

PLH: transmission delay time [s]

C: capacitor value [F]

__
RESET

V

IN<VS L

V

IN>VS H

VCONT Output

L OFF

HON

Connect cont-terminal with V

IN, when it is

not used.

RESET pin output delay time can be set by

the capacitance connected to the Cd pin.

Equivalent Circuit Diagram