September 1993 3
Philips Semiconductors Product specification
Octal bus transceiver/register; 3-state 74HC/HCT646
PIN DESCRIPTION
PIN NO. SYMBOL NAME AND FUNCTION
1CP
AB
A to B clock input (LOW-to-HIGH, edge-triggered)
2S
AB
select A to B source input
3 DIR direction control input
4, 5, 6, 7, 8, 9, 10, 11 A
0
to A
7
A data inputs/outputs
12 GND ground (0 V)
20, 19, 18, 17, 16, 15, 14, 13 B
0
to B
7
B data inputs/outputs
21
OE output enable input (active LOW)
22 S
BA
select B to A source input
23 CP
BA
B to A clock input (LOW-to-HIGH, edge-triggered)
24 V
CC
positive supply voltage
Fig.1 Pin configuration. Fig.2 Logic symbol. Fig.3 IEC logic symbol.
