© 2000 Fairchild Semiconductor Corporation

DS009568

www.fairchildsemi.com

April 1988

Revised October 2000

74F579

8-Bit Bidirectional Binary Counter with 3-STATE Outputs

General Description

The 74F579 is a fully synchronous 8-stage up/down

counter with multiplexed 3-STATE I/O ports for bus-ori-

ented applications. It features a preset capability for pro-

grammable operation, carry lookahead for easy cascading

and a U/D input to control the direction of counting. All state

changes, whether in counting or parallel loading, are initi-

ated by the rising edge of the clock.

Features

s Multiplexed 3-STATE I/O ports

s Built-in lookahead carry capability

s Count frequency 100 MHz typical

s Supply current 75 mA typical

s Guaranteed 4000V minimum ESD protection

Ordering Code:

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

Logic Symbol

Connection Diagram

Order Number

Package Number

Package Description

74F579SC

M20B

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

74F579SJ

M20D

20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide

74F579PC

N20A

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