74HC4538D
1
CMOS Digital Integrated Circuits Silicon Monolithic
74HC4538D
74HC4538D
74HC4538D
74HC4538D
Start of commercial production
2016-05
1.
1.
1.
1. Functional Description
Functional Description
Functional Description
Functional Description
• Dual Monostable Multivibrator
2.
2.
2.
2. General
General
General
General
The 74HC4538D is a high speed CMOS MONOSTABLE MULTIVIBRATOR fabricated with silicon gate C
2
MOS
technology.
It achieves the high speed operation similar to equivalent LSTTL while maintaining the CMOS low power
dissipation.
There are two trigger inputs, A input (positive edge input), and B input (negative edge input). These inputs are
valid for a slow rise/fall time signal (t
r
= t
f
= 1 s) as they are schmitt trigger inputs.
After triggering, the output stays in a MONOSTABLE state for the time period determined by the external
resistor and capacitor (R
X
, C
X
). A low level at CD input breaks this STABLE STATE. In the MONOSTABLE
state, if a new trigger is applied, it makes the MONOSTABLE period longer (retrigger mode).
Limitations for C
X
and R
X
are as follows:
External capacitor C
X
.........No limitation
External resistor R
X
...........V
CC
= 2.0 V more than 5 kΩ
V
CC
= 3.0 V more than 1 kΩ
All inputs are equipped with protection circuits against static discharge or transient excess voltage.
3.
3.
3.
3. Features (Note)
Features (Note)
Features (Note)
Features (Note)
(1) High speed: tpd = 25 ns (typ.) at V
CC
= 5 V
(2) Low power dissipation:
Standby state: I
CC
= 4.0 µA (max) at T
a
= 25
Active state: I
CC
= 350 µA (max) at T
a
= 25
(3) Balanced propagation delays: t
PLH
≈ t
PHL
(4) Wide operating voltage range: V
CC(opr)
= 2.0 to 6.0 V
Note: In the case of using only one circuit, CD should be tied to GND, T1T2QQ should be tied to OPEN, the
other inputs should be tied to V
CC
or GND.
2017-01-24
Rev.6.0
©2016 Toshiba Corporation
