DS1691A/DS3691

General Description

The DS1691A/DS3691 are low power Schottky TTL line

drivers designed to meet the requirements of EIA standards

RS-422 and RS-423. They feature 4 buffered outputs with

high source and sink current capability with internal short

circuit protection. A mode control input provides a choice of

operation either as 4 single-ended line drivers or 2 differen-

tial line drivers. A rise time control pin allows the use of an

external capacitor to slow the rise time for suppression of

near end crosstalk to other receivers in the cable. Rise time

capacitors are primarily intended for waveshaping output

signals in the single-ended driver mode. Multipoint applica-

tions in differential mode with waveshaping capacitors is not

allowed.

With the mode select pin low, the DS1691A/DS3691 are

dual-differential line drivers with TRI-STATE outputs. They

supply.

Features

n

Dual RS-422 line driver with mode pin low, or quad

RS-423 line driver with mode pin high

n

TRI-STATE outputs in RS-422 mode

n

Short circuit protection for both source and sink outputs

n

Outputs will not clamp line with power off or in

TRI-STATE

n

100

Ω transmission line drive capability

n

Low I

RS-422:

I

RS-423:

I

I

n

Low current PNP inputs compatible with TTL, MOS and

CMOS

n

Pin compatible with AM26LS30

Connection Diagrams

With Mode Select LOW

(RS-422 Connection)

00578301

Top View

With Mode Select HIGH

(RS-423 Connection)

00578302

Top View

Ordering Information

Order Number

Package Type

NS Package Number

DS3691M

SO Package

M16A

DS3691N

Molded DIP

N16E

For Complete Military Product Specifications, refer to the appropriate SMD or MDS.

DS1691AJ/883

Ceramic DIP

J16A

July 1998

© 2004 National Semiconductor Corporation

DS005783

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