CD54HC4538, CD74HC4538,
CD74HCT4538
Data sheet acquired from Harris Semiconductor
SCHS123
High Speed CMOS Logic Dual Retriggerable
Precision Monostable Multivibrator
June 1998
Features
Description
• Retriggerable/Resettable Capability
The
Harris
CD54HC4538,
CD74HC4538
and
CD74HCT4538 are dual retriggerable/resettable monostable
precision multivibrators for fixed voltage timing applications.
• Trigger and Reset Propagation Delays Independent of
[ /Title
(CD54
HC453
8,
CD74
HC453
8,
CD74
HCT45
38)
/Sub-
ject
R , C
X
X
An external resistor (R ) and an external capacitor (C )
X
X
control the timing and the accuracy for the circuit.
• Triggering from the Leading or Trailing Edge
• Q and Q Buffered Outputs Available
• Separate Resets
Adjustment of R and C provides a wide range of output
X
X
pulse widths from the Q and Q terminals. The propagation
delay from trigger input-to-output transition and the
propagation delay from reset input-to-output transition are
• Wide Range of Output-Pulse Widths
• Schmitt Trigger Input on A and B Inputs
independent of R and C .
X
X
Leading-edge triggering (A) and trailing edge triggering (B)
inputs are provided for triggering from either edge of the
input pulse. An unused “A” input should be tied to GND and
• Retrigger Time is Independent of C
X
• Fanout (Over Temperature Range)
an unused B should be tied to V . On power up the IC is
CC
- Standard Outputs. . . . . . . . . . . . . . . 10 LSTTL Loads reset. Unused resets and sections must be terminated. In
normal operation the circuit retriggers on the application of
each new trigger pulse. To operate in the non-triggerable
mode Q is connected to B when leading edge triggering (A)
is used or Q is connected to A when trailing edge triggering
(B) is used. The period (τ) can be calculated from τ = (0.7)
- Bus Driver Outputs . . . . . . . . . . . . . 15 LSTTL Loads
o
o
• Wide Operating Temperature Range . . . -55 C to 125 C
• Balanced Propagation Delay and Transition Times
(High
Speed
CMOS
Logic
• Significant Power Reduction Compared to LSTTL
Logic ICs
R , C ; R
is 5kΩ. C
is 0pF.
X
X
MIN
MIN
Ordering Information
• HC Types
- 2V to 6V Operation
TEMP. RANGE
o
PKG.
NO.
- High Noise Immunity: N = 30%, N = 30% of V
IL IH CC
PART NUMBER
CD54HC4538F
CD74HC4538E
CD74HCT4538E
CD74HC4538M
CD74HCT4538M
NOTES:
( C)
PACKAGE
at V
= 5V
CC
-55 to 125
-55 to 125
-55 to 125
-55 to 125
-55 to 125
16 Ld CERDIP F16.3
• HCT Types
16 Ld PDIP
16 Ld PDIP
16 Ld SOIC
16 Ld SOIC
E16.3
- 4.5V to 5.5V Operation
- Direct LSTTL Input Logic Compatibility,
E16.3
V = 0.8V (Max), V = 2V (Min)
IL IH
M16.15
M16.15
- CMOS Input Compatibility, I ≤ 1µA at V , V
l
OL OH
Pinout
1. When ordering, use the entire part number. Add the suffix 96 to
obtain the variant in the tape and reel.
CD54HC4538, CD74HC4538, CD74HCT4538
(PDIP, SOIC, CERDIP)
TOP VIEW
2. Wafer and die for this part number is available which meets all
electrical specifications. Please contact your local sales office or
Harris customer service for ordering information.
1C
1
2
3
4
5
6
7
8
16 V
CC
X
1R C
15 2C
X
X
X
1R
1A
14 2R C
X
X
13 2R
12 2A
11 2B
10 2Q
1B
1Q
1Q
9
2Q
GND
CAUTION: These devices are sensitive to electrostatic discharge. Users should follow proper IC Handling Procedures.
File Number 1671.2
Copyright © Harris Corporation 1998
1