© 1999 Fairchild Semiconductor Corporation DS009568 www.fairchildsemi.com
April 1988
Revised August 1999
7
4F579 8-Bi
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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
a73 Multiplexed 3-STATE I/O ports
a73 Built-in lookahead carry capability
a73 Count frequency 100 MHz typical
a73 Supply current 75 mA typical
a73 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