DS3695/DS3695T/DS3696/DS3697

Multipoint RS485/RS422 Transceivers/Repeaters

General Description

The DS3695, DS3696, and DS3697 are high speed differen-

meet the requirements of EIA standard RS485 with extended

common mode range (+12V to −7V), for multipoint data

transmission.

The driver and receiver outputs feature TRI-STATE capabil-

ity. The driver outputs remain in TRI-STATE over the entire

common mode range of +12V to −7V. Bus faults that cause

excessive power dissipation within the device trigger a ther-

mal shutdown circuit, which forces the driver outputs into the

high impedance state. The DS3696 provides an output pin

TS (thermal shutdown) which reports the occurrence of the

thermal shutdown of the device. This is an “open collector”

pin with an internal 10 k

Ω pull-up resistor. This allows the line

fault outputs of several devices to be wire OR-ed.

Both AC and DC specifications are guaranteed over the 0˚C

to 70˚C temperature 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 15 ns driver propagation delays with 2 ns skew (typical)

n Single +5V supply

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 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 Diagrams

Note 1: TS pin was LF (Line Fault) in previous datasheets and reports the occurrence of a thermal shutdown of the device.

DS010408-1

Top View

DS010408-12

Top View

DS010408-13

Top View

Order Number DS3695N, DS3695TN,

DS3696N, or DS3697N

See NS Package Number N08E

May 1998

© 1998 National Semiconductor Corporation

DS010408

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