74HC652 Datasheet, PDF (4/10 Pages) NXP Semiconductors – Octal bus transceiver/register; 3-state

Philips Semiconductors
Octal bus transceiver/register; 3-state
Product specification
74HC/HCT652
FUNCTION TABLE
INPUTS ⁽¹⁾
DATA I/O ⁽²⁾
OPERATION OR FUNCTION
OE_AB OE_BA CP_AB CP_BA S_AB S_BA
L
H H or L H or L X X
L
H
↑
↑
XX
X
H
↑ H or L X X
H
H
↑
↑
LX
L
X H or L ↑
XX
L
L
↑
↑
XL
L
L
X
X XL
L
L
X H or L X H
H
H
X
X
LX
H
H H or L X H X
H
L H or L H or L H H
A₁ THRU A₈
Input
Input
Input
Not specified
Ouput
Ouput
Input
Output
B₁ THRU B₈
Input
Not specified
Output
Input
Input
Input
Output
Output
HC/HCT652
Isolation
Store A and B data
Store A, Hold B
Store A in both registers
Hold A, Store B
Store B in both registers
Real Time B Data to A Bus
Stored B Data to A Bus
Real Time A Data to B Bus
Stored A Data to B Bus
Stored A Data to B Bus and
Stored B Data to A Bus
Notes
1. H = HIGH voltage level
L = LOW voltage level
X = don’t care
↑ = LOW-to-HIGH transition
2. The data output functions may be enabled or disabled by various signals at OE_AB and OE_BA inputs. Data input
functions are always enabled, i.e., data at the bus inputs will be stored on every LOW-to-HIGH transition on the clock
inputs.
Fig.4 Functional diagram.
September 1993
4