74HC195 Datasheet, PDF (4/9 Pages) NXP Semiconductors – 4-bit parallel access shift register

Philips Semiconductors
4-bit parallel access shift register
Product specification
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
OPERATING MODES
asynchronous reset
shift, set first stage
shift, reset first stage
shift, toggle first stage
shift, retain first stage
parallel load
INPUTS
OUTPUTS
MR CP PE
J
K D_n
Q₀
Q₁
Q₂ Q₃ Q₃
L
X
X
X
XX
L
L
L
L
H
H
↑
h
h
hX
H
q0 q1 q2 q2
H
↑
h
l
lX
L
q0 q1 q2 q2
H
↑
h
h
lX
q0
q0 q1 q2 q2
H
↑
h
l
hX
q0
q0 q1 q2 q2
H
↑
l
X
X d_n
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
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