ST7537HS1

HOME AUTOMATION MODEM

June 1995

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RSTO

RxD

TxD

CD

Rx/Tx

WD

PAFB

ATO

PABC

PABC

TEST1

TEST2

TxIFI

PIN CONNECTIONS

PLCC28

(Plastic Chip Carrier)

ORDER CODE : ST7537HS1

.

HALF DUPLEX ASYNCHRONOUS 2400bps

FSK MODEM

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Tx CARRIER FREQUENCY SYNTHESIZED

FROM EXTERNAL CRYSTAL

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LOW DISTORTION Tx SIGNAL

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CARRIER DETECTION

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WATCH-DOG INPUT

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RESET AND MASTER CLOCK OUTPUTS

FOR MICROCONTROLLER

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POWER AMPLIFIER BIAS CURRENT CON-

TROL (HIGH IMPEDANCE IN Rx MODE)

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SIMPLE AND ECONOMICAL APPLICATION

SCHEMATICS

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COMPATIBLE WITH CENELEC EN 50065-1

AND FCC SPECIFICATION

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CARRIER DETECT CLAMPING ON RxD

PROGRAMMABLE (ALLOWING DEMODULA-

TION ON VERY LOW RECEIVE LEVEL,

DESCRIPTION

The ST7537HS1 is a half duplex asynchronous

FSK MODEM designed for home automation com-

munication on the domestic electric mains which

complies with the EN 50065-1 CENELEC stand-

ard.

It mainly operates from a 10V power supply and a

5V power supply for the microcontroller digital in-

terface.

It is interfaced to the power line by an external

driver, and a transformer (see Application Sche-

matic Diagram). Its data transmission rate is

2400 bps and its carrier frequency is 132.45kHz.

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