© 1999 Fairchild Semiconductor Corporation

DS010267

www.fairchildsemi.com

July 1989

Revised August 1999

74F640 • 74F645

Octal Bus Transceiver with 3-STATE Outputs

General Description

These devices are octal bus transceivers designed for

asynchronous two-way data flow between the A and B bus-

ses. Both busses are capable of sinking 64 mA, have 3-

STATE outputs, and a common output enable pin. The

direction of data flow is determined by the transmit/receive

(T/R) input. The 74F645 is a high speed/low power version

of the 74F245. The 74F640 is an inverting option of the

74F645.

Features

s Designed for asynchronous two-way data flow between

busses

s Outputs sink 64 mA

s Transmit/receive (T/R) input controls the direction of

data flow

s 74F645 is a lower power, faster version of the 74F245

s 74F640 is an inverting option of the 74F645

Ordering Code:

Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.

Logic Symbol

Connection Diagram

Order Number

Package Number

Package Description

74F640SC

M20B

20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide

74F640PC

N20A

20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide

74F645PC

N20A

20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide