74hct191 NXP Semiconductors, 74hct191 Datasheet - Page 4

• Manufacturer Part Number: 74hct191
• Description: Presettable Synchronous 4-bit Binary Up/down Counter
• Manufacturer: NXP Semiconductors

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