MSM7577

¡ Semiconductor

3/8

PIN DESCRIPTION

Pin No.

Name

I/O

Description

1

TAUD

O

Output pin of transmitting voice.

2

AN2

I

Receive voice input.

Gain control should be connected by a resistor between AN2 pin RCV2 pin.

4

RCV2

O

Output pin of receiving voice.

Gain control should be connected by a resistor between AN2 and RCV2 pin.

RCV2 signal is opposite phase to RCV1 signal.

6

NC

—

No Connection.

7

RAUD

I

Receive voice input.

8

GND

—

Ground (0 V).

9

10

11

ATT0

ATT1

ATT2

I

Volume control.

ATT2

ATT1

ATT0

Loss level (dB)

0

0

0

0 ±0.3

0

0

1

–2 ±0.3

0

1

0

–4 ±0.3

0

1

1

–7 ±0.3

1

0

0

–10 ±0.3

1

0

1

–13 ±0.3

1

1

0

–16 ±0.3

1

1

1

–19 ±0.3

12

ATTE

I

Mute signal input.

H : Mute mode

L : Operating mode

13

AN3

I

Gain control and frequency responce control.

Gain control should be controlled by a resistor between AN3 and AO3.

14

MIC

I

Input pin of Microphone signal.

15

AO3

O

Gain control and frequency responce control.

Gain control should be controlled by a resistor between AN3 and AO3.

16

—

Power supply (+3 V).

3

PD

1

Power down control.

H : Power down

L : Power on

5

RCV1

O

Receive voice input.

RCV1 signal is opposite phase to RCV2 signal.