HD74HC374/HD74HC534
Octal D-type Flip-Flops (with 3-state outputs)
Octal D-type Flip-flops (with inverted 3-state outputs)
Description
These devices are positive edge triggered flip-flops. The difference between HD74HC374 and
HD74HC534 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
•
High Speed Operation: t
pd
(Clock to Q) = 18 ns typ (C
L
= 50 pF)
•
High Output Current: Fanout of 15 LSTTL Loads
•
Wide Operating Voltage: V
CC
= 2 to 6 V
•
Low Input Current: 1 µA max
•
Low Quiescent Supply Current: I
CC
(static) = 4 µA max (Ta = 25°C)
Function Table
Output Control
L
L
L
H
X :
Z :
L
X
Clock
D
H
L
X
X
HD74HC374
Q
H
L
No change
Z
HD74HC534
Q
L
H
No change
Z
irrelevant
off (high-impedance) state of a 3-state output.
HITACHI [ HITACHI SEMICONDUCTOR ]
