GL6552

3

Pin Description

No.

Symbol

Function

1

Output terminal of bias circuit (Band Gap of reference). It is an internal

reference voltage used for supplying a constant voltage to the compressor

and the expander.

2

EXP IN

Expander input terminal

3

EXP RECT

External rectifing capacitor is connected to this terminal. Attack and decay

time of expander is determined by capacitor.

4

EXP OUT

Expander output terminal

5

MUTE

EXP

It is an expander mute terminal of a compander.

“L” state – expander mute is executed.

“H” state – expander is executed.

6

MUTE

COMP

It is an compander mute terminal of a compander.

“L” state – compressor mute is executed.

“H” state – compressor is executed.

7

GND

Ground terminal

8

COMP IN

Compressor Mic Amp noninverting input terminal. It is used as input

terminal for voice signal.

9

COMP NF

Compressor Mic Amp inverting input terminal. It is used for determining

Mic Amp gain by resistor

10

COMP RECT

External rectifing capacitor is connected to this terminal. Attack and decay

time of expander is determined by capacitor.

11

C-ACF

Feedback coupling capacitor is connected to this terminal. Low cut-off

frequency of compressor is determined by this capacitor.

12

COMP OUT

Compressor output terminal.

13

ALC

It is a reference voltage input terminal of ALC. ALC circuit may be turned

off according to the ALC reference voltage.

14

VCC

Supply voltage terminal