Datasheet

December 1990 4
Philips Semiconductors Product specification
Presettable synchronous 4-bit binary
up/down counter
74HC/HCT191
PIN DESCRIPTION
PIN NO. SYMBOL NAME AND FUNCTION
3, 2, 6, 7 Q
0
to Q
3
flip-flop outputs
4
CE count enable input (active LOW)
5
U/D up/down input
8 GND ground (0 V)
11
PL parallel load input (active LOW)
12 TC terminal count output
13
RC ripple clock output (active LOW)
14 CP clock input (LOW-to-HIGH, edge triggered)
15, 1, 10, 9 D
0
to D
3
data inputs
16 V
CC
positive supply voltage
Fig.1 Pin configuration. Fig.2 Logic symbol. Fig.3 IEC logic symbol.