Philips Semiconductors
Product specification
4-bit parallel access shift register
74HC/HCT195
Fig.4 Functional diagram.
APPLICATIONS
• Serial data transfer
• Parallel data transfer
• Serial-to-parallel data transfer
• Parallel-to-serial data transfer
FUNCTION TABLE
INPUTS
OUTPUTS
OPERATING MODES
MR
CP
PE
J
K
Dn
Q0
Q1
Q2
Q3
Q3
asynchronous reset
L
X
X
X
X
X
L
L
L
L
H
shift, set first stage
H
H
H
H
↑
↑
↑
↑
h
h
h
h
h
l
h
l
h
l
l
X
X
X
X
H
L
q0
q0
q0
q0
q0
q0
q1
q1
q1
q1
q2
q2
q2
q2
q2
q2
q2
q2
shift, reset first stage
shift, toggle first stage
shift, retain first stage
h
parallel load
H
↑
l
X
X
dn
d0
d1
d2
d3
d3
Notes
1. H = HIGH voltage level
h = HIGH voltage level one set-up time prior to the LOW-to-HIGH clock transition
L = LOW voltage level
I = LOW voltage level one set-up time prior to the LOW-to-HIGH clock transition
q, d = lower case letters indicate the state of the referenced input (or output) one set-up time prior to the
LOW-to-HIGH clock transition
X = don’t care
↑ = LOW-to-HIGH clock transition
December 1990
4
NXP [ NXP ]
