SN65LBC179A, SN75LBC179A

LOW-POWER DIFFERENTIAL LINE DRIVER AND RECEIVER PAIRS

SLLS377C – MAY 2000 – REVISED JUNE 2001

1

POST OFFICE BOX 655303

up to 30 Mbps

HBM

Requirements ...700

µA Max

to 12 V

TIA/EAI-485-A and ISO8482: 1987(E)

Limiting

description

The

SN65LBC179A

and

SN75LBC179A

differential driver and receiver pairs are monolithic

integrated circuits designed for bidirectional data

communication over long cables that take on the

characteristics of transmission lines. They are

balanced, or differential, voltage mode devices

that

are

compatible

with

ANSI

standard

TIA/EIA-485-A and ISO 8482:1987(E). The A

version offers improved switching performance

over

its

predecessors

without

sacrificing

significantly more power.

The SN65LBC179A and SN75LBC179A combine

a differential line driver and differential input line

receiver and operate from a single 5-V supply. The

driver differential outputs and the receiver

differential inputs are connected to separate

terminals for full-duplex operation and are

designed to present minimum loading to the bus

making them suitable for point-to-point or multipoint data bus applications. The devices also provide positive-

and negative-current limiting and thermal shutdown for protection from line fault conditions.

The SN65LBC179A is characterized over the industrial temperature range of – 40

°C to 85°C. The

SN75LBC179A is characterized for operation over the commercial temperature range of 0

°C to 70°C.

† Signaling rate by TIA/EIA-485-A definition restrict transition times to 30% of the bit length, and much higher signaling rates may be achieved

without this requirement as displayed in the TYPICAL CHARACTERISTICS of this device.

Copyright

 2001, Texas Instruments Incorporated

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

LinBiCMOS is a trademark of Texas Instruments.

logic diagram (positive logic)

R

D

B

A

Z

Y

7

8

6

5

2

3

INPUT

D

OUTPUTS

Y

Z

DRIVER

DIFFERENTIAL INPUTS

A–B

VID ≥ 0.2 V

– 0.2 V < VID < 0.2 V

VID ≤ – 0.2 V

Open circuit

OUTPUT

R

H

?

L

H

RECEIVER

H = high level,

L = low level,

? = indeterminate

Function Tables

1

2

3

4

8

7

6

5

R

D

GND

A

B

Z

Y

SN65LBC179AD (Marked as BL179A)

SN65LBC179AP (Marked as 65LBC179A)

SN75LBC179AD (Marked as LB179A)

SN75LBC179AP (Marked as 75LBC179A)

(TOP VIEW)

H

L

Open

H

L

H

L

H

L