MITSUMI
IC for Headphone Stereos MM1376
IC for Headphone Stereos
Monolithic IC MM1376
Outline
This IC was developed for use in 3V headphone stereos, and combines all the basic audio circuitry for
headphone stereos on a single chip.
Recently hearing impairment caused by the high volumes of headphone stereos has become a problem, and
there has been strong demand for functions for limiting loud volumes in the sets themselves. This IC
incorporates an ALC circuit and has functions to hold the output from the headphone to a fixed level; it also
eliminates the ordinary electronic governor circuit in order to accommodate trends toward thinner sets, as
seen in the adoption of BSL motors.
Package
1. Configuration: Pre-and power amps, ALC circuit
2. Internal tape selector: A selector switch allows the user to select between normal and metal tapes.
3. Internal OCL circuit: No need for large-capacitance output capacitor
4. Preamp off function: Preamp alone can be turned off for connection to radio etc.
5. MM1376CF amp gain takes Dolby noise reduction into account
Package
SOP-22
Pin Assignment
1
2
3
4
22 21 20 19 18 17 16 15 14 13 12
5
6
1 2 3 4 5 6 7 8 9 10 11
SOP-22
7
8
9
10
11
COM1
Preamp non-inverted input
Preamp inverted input
Metal switching output
Preamp output
Power input
Rectifier pin
ALC control
Power output
COM2
GND1
12
13
14
15
16
17
18
19
20
21
22
Power output
V
CC
Ripple filter
Preamp off
Tape selector
Power input
Preamp output
Metal switching output
Preamp inverted input
Preamp non-inverted input
GND2
Absolute Maximum Ratings
Item
Operating temperature
Storage temperature
Power supply current
Power consumption
Symbol
T
OPR
T
STG
V
CC
Pd
Ratings
-10~+65
-40~+125
-0.3~+7.5
350
Units
擄
C
擄
C
V
mW
1
2
3
