Data is entered serially through one of two inputs (D
Dsb); either input can be used as an active HIGH enable for
data entry through the other input.
Both inputs must be connected together or an unused
input must be tied HIGH.
Data shifts one place to the right on each LOW-to-HIGH
transition of the clock (CP) input and enters into Q0, which
GENERAL DESCRIPTION
The 74HC/HCT164 are high-speed Si-gate CMOS devices
and are pin compatible with low power Schottky TTL
(LSTTL). They are specified in compliance with JEDEC
standard no. 7A.
is the logical AND of the two data inputs (Dsa,Dsb) that
existed one set-up time prior to the rising clock edge.
A LOW level on the master reset (MR) input overrides all
other inputs and clears the register asynchronously,
forcing all outputs LOW.
The 74HC/HCT164 are 8-bit edge-triggered shift registers
with serial data entry and an output from each of the eight
stages.
QUICK REFERENCE DATA
GND = 0 V; T
= 25 °C; tr= tf= 6 ns
amb
SYMBOLPARAMETERCONDITIONS
t
PHL
f
max
C
C
I
PD
/ t
PLH
propagation delay
CP to Q
MR to Q
n
n
CL= 15 pF; VCC= 5 V
maximum clock frequency7861MHz
input capacitance3.53.5pF
power dissipation capacitance per
notes 1 and 2
package
TYPICAL
HCHCT
12
11
14
16
ns
ns
4040pF
sa
UNIT
or
Notes
1. C
is used to determine the dynamic power dissipation (PDin µW):
PD
PD= CPD× V
2
× fi+∑(CL× V
CC
2
× fo) where:
CC
fi= input frequency in MHz
fo= output frequency in MHz
∑ (CL× V
2
× fo) = sum of outputs
CC
CL= output load capacitance in pF
VCC= supply voltage in V
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 = lower case letters indicate the state of the referenced input one set-up time prior to the