HD74HC4538
Dual Precision Retriggerable/Resettable Monostable
Multivibrators
Description
Each multivibrator features both a negative, A, and a positive, B, transition triggered input, either of which
can be used as an inhibit input. Also included is a clear input that when taken low resets the one short. The
HD74HC4538 is retriggerable. That is, it may be triggered repeatedly while their outputs are generating a
pulse and the pulse will be extended.
Pulse width stability over a wide range of temperature. The output pulse equation is simply: t
w
= 0.7 (R)
(C).
Features
• High Speed Operation: t
pd
(A or B to Y) = 22 ns typ (C
L
= 50 pF)
• High Output Current: Fanout of 10 LSTTL Loads
• Wide Operating Voltage: V
CC
= 2 to 6 V
• Low Input Current: 1 µA max
• Low Quiescent Supply Current
Function Table
Inputs Outputs
C
D
ABQQ
LXXLH
HL
H H
HH Not triggered
H L Not triggered
X : Irrelevant