HD74HCT374/HD74HCT534
Octal D-type Flip-Flops (with 3-state outputs)/
Octal D-type Flip-Flops (with inverted 3-state outputs)
Description
These device are positive edge triggered flip-flops. The difference between HD74HCT374 and
HD74HCT534 is only that the former is a true outputs and the latter is a false outputs. Data at the D inputs,
meeting the setup and hold time requirements, are transferred to the Q outputs on positive going transitions
of the clock (CK) input. When a high logic level is applied to the output control (OC) input, all outputs go
to a high impedance state, regardless of what signals are present at the other inputs and the state of the
storage elements.
Features
LSTTL Output Logic Level Compatibility as well as CMOS Output Compatibility
High Speed Operation: t
pd
(Clock to Q) = 15 ns typ (C
L
= 50 pF)
High Output Current: Fanout of 15 LSTTL Loads
Wide Operating Voltage: V
CC
= 4.5 to 5.5 V
Low Input Current: 1 A max
Low Quiescent Supply Current: I
CC
(static) = 4 A max (Ta = 25C)
Function Table
Output Control
Clock
D
HD74HCT374
Q
HD74HCT534
Q
L
H
H
L
L
L
L
H
L
L
X
No change
No change
H
X
X
Z
Z
X :
Irrelevant
Z
:
Off (high-impedance) state of a 3-state output.
PDF 
ZIP
