DS75176B/DS75176BT

Multipoint RS-485/RS-422 Transceivers

General Description

bus/line transceiver designed to meet the requirements of

EIA standard RS485 with extended common mode range

(+12V to −7V), for multipoint data transmission. In addition, it

is compatible with RS-422.

The driver and receiver outputs feature TRI-STATE capabil-

ity, for the driver outputs over the entire common mode

range of +12V to −7V. Bus contention or fault situations that

cause excessive power dissipation within the device are

handled by a thermal shutdown circuit, which forces the

driver outputs into the high impedance state.

DC specifications are guaranteed over the 0 to 70˚C tem-

perature and 4.75V to 5.25V supply voltage range.

Features

n

Meets EIA standard RS485 for multipoint bus

transmission and is compatible with RS-422.

n

Small Outline (SO) Package option available for

minimum board space.

n

22 ns driver propagation delays.

n

Single +5V supply.

n

ground difference between devices on the bus.

n

Thermal shutdown protection.

n

High impedance to bus with driver in TRI-STATE or with

power off, over the entire common mode range allows

the unused devices on the bus to be powered down.

n

Pin out compatible with DS3695/A and SN75176A/B.

n

Combined impedance of a driver output and receiver

input is less than one RS485 unit load, allowing up to 32

transceivers on the bus.

n

70 mV typical receiver hysteresis.

Connection and Logic Diagram

00875901

Top View

Order Number DS75176BN, DS75176BTN, DS75176BM or DS75176BTM

See NS Package Number N08E or M08A

July 2004

© 2004 National Semiconductor Corporation

DS008759

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