SN54BCT640, SN74BCT640

OCTAL BUS TRANSCEIVERS

WITH 3-STATE OUTPUTS

SCBS025C – SEPTEMBER 1988 – REVISED APRIL 1994

Copyright

2–1

POST OFFICE BOX 655303

Substantially Reduces Standby Current

Circuitry

Loading Effects

Per MIL-STD-883C, Method 3015

Small-Outline (DW) Packages, Ceramic

Chip Carriers (FK) and Flatpacks (W), and

Plastic and Ceramic 300-mil DIPs (J, N)

description

The

′BCT640 bus transceiver is designed for

asynchronous

communication

between

data

buses. These devices transmit data from the A

bus to the B bus or from the B bus to the A bus

depending upon the level at the direction-control

(DIR) input. The output-enable (OE) input can be

used to disable the device so that the buses are

effectively isolated.

The SN54BCT640 is characterized for operation

over the full military temperature range of – 55

°C

to 125

°C. The SN74BCT640 is characterized for

operation from 0

°C to 70°C.

FUNCTION TABLE

INPUTS

OPERATION

OE

DIR

OPERATION

L

L

B data to A bus

L

HA data to B bus

H

X

Isolation

1

2

3

4

5

6

7

8

9

10

20

19

18

17

16

15

14

13

12

11

DIR

A1

A2

A3

A4

A5

A6

A7

A8

GND

OE

B1

B2

B3

B4

B5

B6

B7

B8

SN54BCT640 ...J OR W PACKAGE

SN74BCT640 . . . DW OR N PACKAGE

(TOP VIEW)

32

1 20 19

9 10 11 12 13

4

5

6

7

8

18

17

16

15

14

B1

B2

B3

B4

B5

A3

A4

A5

A6

A7

SN54BCT640 . . . FK PACKAGE

(TOP VIEW)

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.