Mode Selection

Mode

REC

ON/

OFF

LINE

ON/

OFF

PWR

ON/

OFF

INPUT

MUTE

SW1/

SW11

ICM

REC

SW2

ICM

PLAY

SW3

LINE

SW4

MIC

SW5

MUTE

SW6

PRE/

OGM

SW7

MONI

/OGM

SW8

LINE

SW9

PWR

SW10

PRE/

EQ

D1

D0

MUTE

×××××

HIGH

××××

0

×××××

ICM REC

HIGH LOW HIGH HIGH HIGH

LOW

1010

1

11010

2WAY REC

HIGH LOW LOW HIGH HIGH

LOW

1010

1

11000

DICT REC

HIGH LOW LOW HIGH LOW

LOW

1001

1

11000

2WAY BEEP

HIGH HIGH HIGH LOW HIGH

LOW

1010

1

01110

ICM OUT

LOW HIGH HIGH LOW LOW

LOW

0100

1

11111

ICM PLAY

LOW LOW HIGH LOW LOW

LOW

0100

1

11011

OGM REC

LOW LOW LOW HIGH LOW

LOW

0001

1

11000

OGM CHANGE

LOW LOW HIGH HIGH HIGH

LOW

0010

1

11010

OGM OUT

LOW HIGH HIGH LOW HIGH

LOW

0010

1

01110

OGM PLAY

LOW LOW HIGH LOW HIGH

LOW

0010

1

01010

ROOM MONI

LOW HIGH LOW HIGH LOW

LOW

0001

1

11100

ROOM OUT

LOW LOW HIGH HIGH HIGH

LOW

0010

1

11010

VOICE SELE

LOW HIGH HIGH HIGH HIGH

LOW

0010

1

10110

Conversation

recording

HIGH HIGH HIGH HIGH HIGH

LOW

1010

1

10110

Notes

2WAY BEEP : LINE OUT –6 dB

1 = ON and 0 = OFF (SW1 to SW5, SW8, SW9 and SW11)

Pin Functions

Pin No.

Pin name

Functions

1

BIAS/GAIN

Bias. Recording amplifier gain and recording bias current controled by external

resistor.

2

ICM

Incoming head input/output

3PB NF

Playback amplifier feedback. Receives negative feedback input from PRE OUT

(pin 8).

4

GND

Preamplifier ground

5

LINE

Line input

6

MIC

Microphone input

7

PRE NF

Preamplifier feedback. Receives negative feedback input from PRE OUT (pin 8).

8

PRE OUT

Preamplifier/playback amplifier output

9

ALC. CT

Automatic level control time constant adjust input

10

SIG IN

Preamplifier/playback amplifier output signal input

11

OGM/BEEP

Outgoing message/beep input

12

FIL NF

Filter amplifier negative feedback input

13

FIL OUT

Filter amplifier output

14

V. REF

Internal reference voltage output (Approx. 2.2 V)

15

Preamplifier supply

16

P.GND

Power amplifier ground

17

PWR OUT

Power amplifier output

18

Power amplifier supply

19

D.C

20

PWR IN

Power amplifier input

21

PWR MONI

Power amplifier monitor output

22

LINE OUT

Line amplifier output

23

TH

Voice-operated switch (VOX) threshold adjust input. VOX sensitivity can be adjusted

24

VOX. C/MUTE

Voice-operated switch (VOX) detection and mute control

25

VOX

Voice-operated switch (VOX) open-collector output

26

D0

Incoming message, line, microphone and outgoing message/beep analog switch

control inputs.

27

D1

28

PWR ON/OFF

Power amplifier ON/OFF analog switch control input

29

LINE ON/OFF

Line amplifier ON/OFF analog switch control input

30

REC ON/OFF

Recording amplifier ON/OFF analog switch control input

LA2806M

No. 3852 - 5/11