SN54ALS645A, SN54AS645, SN74ALS645A, SN74AS645
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS

SDAS278 - JANUARY 1995

features

• Bidirectional Bus Transceivers in High-Density 20-Pin Packages
• True Logic
• 3-State Outputs
• 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 on the level at the direction-control (DIR) input. The output-enable input can be used to disable the device so that the buses are effectively isolated.

The -1 version of the SN74ALS645A is identical to the standard version, except that the recommended maximum I_OL is increased to 48 mA. There is no -1 version of the SN54ALS645A.

The SN54ALS645A and SN54AS645 are characterized for operation over the full military temperature range of -55°C to 125°C. The SN74ALS645A and SN74AS645 are characterized for operation from 0°C to 70°C.