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EM91810A/B

TONE/PULES SWITCHABLE DIALER WITH LCD INTERFACE

* This specification are subject to be changed without notice.

10.1.1997

GENERAL DESCRIPTION

The EM91810A/B are Tone/Pulse switchable dialer which are fabricated in CMOS technology with wide

operating voltage for both tone and pulse mode, and consumes very low memory retention current in ON-HOOK

state. EM91810A/B also provide SDO (serial data output) function to drive LCD driver (EM32100, EM32116,

EM32117) and voice synthesizer.

FEATURES

• Tone/pulse switchable dialer.

• One 32-digit last number redial memory.

• Pulse to tone (P

→T) is provided for PBX operation.

• Flash key is available.

• Minimum tone duration is 98ms or 83ms.

• Minimum intertone pause is 98ms or 83ms.

• Uses 3.579545 MHz crystal or ceramic resonator.

• Many options can be selected.

Mode (10 PPS ; 20 PPS ; Tone)

M/B ratio (40 : 60 ; 33 : 66)

Pause time (3.6s)

• Flash function (RESET)

P

→T pause time (3.6s)

Flash time (600ms; 300ms; 100ms; or 80ms).

• Mixed dialing.

• Handfree function is provided for speaker phone application.

• Power on reset circuit is provided.

• Package in DIP18 or DIP20.

• SDO function that is supported to drive LCD driver (EM32100) and voice synthesizer to indicate dialing

number.

• Key tone function is provided.

PIN ASSIGNMENTS

EM91810A/B

TONE/PULSE SWITCHABLE DIALER WITH LCD INTERFACE

C2

C3

C4

C1

OSCI

OSCO

XMUTE

SDO

EM91810A

18

17

16

15

14

13

12

11

10

1

2

3

4

5

6

7

8

9

R3

R2

R1

R4

TONE

PO

HKS

V

KT

DD

SS

V

C2

C3

C4

C1

OSCI

OSCO

XMUTE

HFI

SDO

20

19

18

17

16

15

14

13

12

11

1

2

3

4

5

6

7

8

9

10

EM91810B

SS

V

DD

R3

R2

R1

R4

TONE

PO

HKS

V

HFO

KT