© 1999 Fairchild Semiconductor Corporation DS009934 www.fairchildsemi.com
November 1988
Revised November 1999
7
4
AC
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Stage
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B
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C
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74AC169
4-Stage Synchronous Bidirectional Counter
General Description
The AC169 is fully synchronous 4-stage up/down counter.
The AC169 is a modulo-16 binary counter. It features a
preset capability for programmable operation, carry looka-
head for easy cascading and a U/D input to control the
direction of counting. All state changes, whether in count-
ing or parallel loading, are initiated by the LOW-to-HIGH
transition of the Clock.
Features
a73 I
CC
reduced by 50%
a73 Synchronous counting and loading
a73 Built-In lookahead carry capability
a73 Presettable for programmable operation
a73 Outputs source/sink 24 mA

Ordering Code:
Device also available in Tape and Reel. Specify by appending suffix letter “X” to the ordering code.
Logic Symbols
IEEE/IEC
Connection Diagram
Pin Descriptions
FACT is a trademark of Fairchild Semiconductor Corporation.
Order Number Package Number Package Description
74AC169SC M16A 16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150” Narrow Body
74AC169SJ M16D 16-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
74AC169MTC MTC16 16-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide
74AC169PC N16E 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300” Wide
Pin Names Description
CEP Count Enable Parallel Input
CET Count Enable Trickle Input
CP Clock Pulse Input
P
0
–P
3
Parallel Data Inputs
PE Parallel Enable Input
U/D Up-Down Count Control Input
Q
0
–Q
3
Flip-Flop Outputs
TC Terminal Count Output