MITSUMI
High-Precision Three-Pin Regulator MM1257
High-Precision Three-Pin Regulator
Monolithic IC MM1257
Outline
This IC is a high-precision high-voltage stabilized power supply device which stands out from ordinary low-
saturation three-pin regulators.
It can be used at a wide range of output voltages, from 3V to 12V, delivering output currents up to 100mA. It
is one of a series of devices available at lower prices than previous regulators.
Features
1. Input current
27V max.
2. Output noise voltage
200Vrms typ.
3. Maximum output current
100mA max.
4. No-load input current
500A typ.
5. Thermal shutdown circuit provided
6. Output voltage ranks
A : 12V2% E : 6V2%
B : 10V2% F : 5V2%
C : 9V2%
G : 3V2%
D : 8V2%
Package
TO-92A (MM1257 T)
MMP-4A (MM1257 M)
*
The output voltage rank appears in the boxes.
Applications
1. Handheld computers
2. Portable transceivers
3. Cordless phones
1
2
4
3
MMP-4A
(TOP VIEW)
1
2
3
TO-92A
Pin Assignment
1
NC
2
V
IN
3
V
OUT
4
GND
1
V
OUT
2
GND
3
V
IN
MITSUMI
High-Precision Three-Pin Regulator MM1257
Absolute Maximum Ratings
(Ta=25C)
Item
Symbol
Ratings
Units
Storage temperature
T
STG
-40~+125 C
Operating temperature
T
OPR
-20~+75
C
Power supply current
V
CC
max.
27
V
Output current
I
OUT
100 mA
Maximum Ratings
Pd
200 (MMP-4A), 300 (TO-92A)
mW
Recommended Operating Conditions
Item
Symbol
Ratings
Units
Input voltage
V
IN
7~27
V
Output current
I
O
1~100
mA
Pin Description
Pin no.
Pin name
Function
1
N.C
N.C
2
V
IN
Power supply input pin
3
V
OUT
Regulator output pin
4
GND
GND
Equivalent Circuit Diagram
PDF 
ZIP