Connection Diagrams
Pin Assignment
for DIP and Flatpak
Pin Assignment
for LCC
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DS100276-4
Logic Diagram
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Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays.
data on the P0–P3 inputs enters the flip-flops on the next ris-
ing edge of the Clock. In order for counting to occur, both
CEP and CET must be LOW and PE must be HIGH; the U/D
input then determines the direction of counting. The Terminal
Count (TC) output is normally HIGH and goes LOW, pro-
vided that CET is LOW, when a counter reaches zero in the
Count Down mode or reaches 15 in the Count Up mode. The
TC output state is not a function of the Count Enable Parallel
(CEP) input level. If an illegal state occurs, the ’AC169 will
return to the legitimate sequence within two counts. Since
Functional Description
The ’AC/’ACT169 uses edge-triggered J-K-type flip-flops
and have no constraints on changing the control or data in-
put signals in either state of the Clock. The only requirement
is that the various inputs attain the desired state at least a
setup time before the rising edge of the clock and remain
valid for the recommended hold time thereafter. The parallel
load operation takes precedence over the other operations,
as indicated in the Mode Select Table. When PE is LOW, the
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