Bidirectional Bus Transceivers in

High-Density 20-Pin Packages

Inverting Logic

Package Options Include Plastic

Small-Outline (DW) Packages, Ceramic

Chip Carriers (FK), and Standard Plastic (N)

and Ceramic (J) 300-mil DIPs

description

These octal bus transceivers are designed for

asynchronous two-way 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 -1 version of the SN74ALS640B is identical to

the standard version, except that the

recommended maximum IOL for the -1 version is

increased to 48 mA. There is no -1 version of the

SN54ALS640B.

The SN54ALS640B and SN54AS640 are

characterized for operation over the full military

temperature range of –55°C to 125°C. The

SN74ALS640B and SN74AS640 are

characterized for operation from 0°C to 70°C.