HCF4022B Datasheet, PDF (6/11 Pages) STMicroelectronics – OCTAL COUNTER WITH 8 DECODED OUTPUTS

HCF4022B
TYPICAL APPLICATIONS
DIVIDE BY N COUNTER(N < 10) WITH
DECODED OUTPUTS
TEST CIRCUIT
When the N^th decoded output is reached (N^th
clock pulse) the S-R flip-flop (constructed from two
NOR gates of the HCF4001B) generates a reset
pulse which clears the HCF4022B to its zero
count. At this time, if the N^th decoded output is
greater than or equal to 6, the C_OUT line goes high
to clock the next HCF4022B counter section. The
"0" decoded output also goes high at this time.
Coincidence of the clock low and decoded "0"
output high resets the S-R flip-flop to enable the
HCF4022B. If the N^th decoded output is less than
6, the COUT line will not go high and, therefore,
cannot be used. In this case "0" decoded output
may be used to perform the clocking function for
the next counter.
C_L = 50pF or equivalent (includes jig and probe capacitance)
R_L = 200KΩ
R_T = Z_OUT of pulse generator (typically 50Ω)
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