74HCT4017

Johnson decade counter with 10 decoded outputs

Other names for this product: 74HC, 74hc4017,

Courtesy/Thanks to: Philips Semiconductor

Description: The 74HC/HCT4017 are high-speed Si-gate
CMOS devices and are pin compatible with
the “4017” of the “4000B” series. They
are specified in compliance with JEDEC
standard no. 7A.
The 74HC/HCT4017 are 5-stage Johnson
decade counters with 10 decoded active
HIGH outputs (Q0 to Q9), an active LOW
output from the most significant flip-
flop (Q5-9), active HIGH and active LOW
clock inputs (CP0 and CP1) and an
overriding asynchronous master reset
input (MR).
The counter is advanced by either a LOW-
to-HIGH transition at CP0 while CP1 is
LOW or a HIGH-to-LOW transition at CP1
while CP0 is HIGH (see also function
table).
When cascading counters, the Q5-9
output, which is LOW while the counter
is in states 5, 6, 7, 8 and 9, can be
used to drive the CP0 input of the next
counter.
A HIGH on MR resets the counter to zero
(Q0 = Q5-9 = HIGH; Q1 to Q9 = LOW)
independent of the clock inputs (CP0 and
CP1).
Automatic code correction of the counter
is provided by an internal circuit:
following any illegal code the counter
returns to a proper counting mode within
11 clock pulses.