MC74HC597A Datasheet, PDF (7/12 Pages) ON Semiconductor – 8-Bit Serial or Parallel- Input/Serial-Output Shift Register

MC74HC597A
FUNCTION TABLE
Inputs
Resulting Function
Operation
Reset shift register
Serial Shift/
Reset Parallel Load
L
X
Latch
Clock
L, H,
Shift
Clock
X
Serial
Input
S_A
X
Parallel
Inputs
A−H
X
Latch
Contents
U
Shift
Register
Contents
L
Output
Q_H
L
Reset shift register; load
L
X
parallel data into data latch
X
X
a−h
a−h
L
L
Load parallel data into data H
H
latch
L,H,
X
a−h
a−h
U
U
Transfer latch contents to
H
shift register
L
L, H,
X
X
X
U
LR_N → SR_N
LR_H
Contents of data latch and H
H
L, H, L,H,
X
X
U
U
U
shift register are
unchanged
Load parallel data into data H
L
latch and shift register
X
X
a−h
a−h
a−h
h
Shift serial data into shift
H
H
X
register
Load parallel data into data H
H
latch and shift serial data
into shift register
D
X
D
a−h
*
SR_A = D;
SR_G → SR_H
SR_N → SR_{N + 1}
a−h
SR_A = D;
SR_G → SR_H
SR_N → SR_{N + 1}
LR = latch register contents
SR = shift register contents
* = depends on latch clock input
a−h = data at parallel data inputs A−H
D = data (L, H) at serial data input S_A
U = remains unchanged
X = don’t care
http://onsemi.com
7