SN75LBC179, SN65LBC179, SN65LBC179Q

LOW POWER DIFFERENTIAL LINE DRIVER AND RECEIVER PAIRS

SLLS173F − JANUARY 1994 − REVISED APRIL 2006

1

POST OFFICE BOX 655303

Transmission Over Long Cables

as 30 ns

Requirements of ANSI RS-485 and

ISO 8482:1987(E)

to 12 V

Limiting

description

The

SN65LBC179,

SN65LBC179Q,

and

SN75LBC179 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 meet or

exceed the requirements of industry standards

ANSI RS-485 and ISO 8482:1987(E). Both

devices are designed using TI’s proprietary

LinBiCMOS

 with the low power consumption of

CMOS and the precision and robustness of

bipolar transistors in the same circuit.

The

SN65LBC179,

SN65LBC179Q,

and

SN75LBC179 combine a differential line driver

and differential 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

feature a wide common-mode voltage range

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 line driver shuts down at a junction

temperature of approximately 172

°C.

Copyright

 1994 − 2006, 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)

Y

Z

B

A

R

D

5

6

7

8

2

3

R

D

B

A

Z

Y

7

8

6

5

2

3

† This symbol is in accordance with ANSI/IEEE Std 91-1984

and IEC Publication 617-12.

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

D OR P PACKAGE

(TOP VIEW)

H

L

H

L

L

H