SM8223A

NIPPON PRECISION CIRCUITS—1

NIPPON PRECISION CIRCUITS INC.

FSK Decoder and DTMF Receiver IC

OVERVIEW

The SM8223A is a FSK (Frequency shift keying) decoder and DTMF (Dual tone multi-frequency) receiver IC.

It is fabricated using a CMOS process and features a power-down function for low power dissipation opera-

tion. The FSK decoder and DTMF receiver have the same performance characteristics as dedicated ICs that

using the telephone tip/ring input signal. It also features a ring (call signal) signal detection circuit, making for

easy construction of low power dissipation, high-performance analog telephone-related applications.

FEATURES

s

Both FSK signal caller-ID information services

and DTMF signal caller-ID information services

supported

s

FSK decoder/DTMF receiver auto-select function

s

Ring (call signal) signal detection circuit built-in

s

Serial I/O

s

Input gain adjustment circuit built-in

s

Power-down mode

s

Single supply operation: 3.0V ± 10%

s

3.579545MHz external crystal oscillator fre-

quency

s

Molybdenum-gate CMOS process

APPLICATIONS

s

Telephones, fax machines and modems that sup-

port caller-ID information services

s

Adapters for caller-ID information service func-

tions

s

Telephones, fax machines and modems that sup-

port remote operation functions

ORDERING INFORMATION

PINOUT

(Top view)

PINOUT

(Unit:

µm)

1. Auto-select function operates if the FSK signal conforms to the Bellcore GR-30-CORE standard.

D e vice

P a ck ag e

SM8223A

16-pin DIP

CF8223A

Chip

P ad size : 90

µm × 90µm

1

9

16

8

TIP

RING

GS

AGND

RDIN

RDRC

VDD

DOUT

FSK/DTMF

IC

OSCIN

DV

RDET

PDWN

OSCOUT

GND

GS

(0, 0)

(2810, 3160)

DOUT

RDET

AGND

RDIN

RDRC

PDWN

GND OSCOUT

FSK/DTMF

IC

OSCIN

RING

TIP

VDD

DV