HCF4538B
DUAL MONOSTABLE MULTIVIBRATOR
s
s
s
s
s
s
s
s
s
s
s
s
RETRIGGERABLE/RESETTABLE
CAPABILITY
TRIGGER AND RESET PROPAGATION
DELAYS INDEPENDENT OF R
X
, C
X
TRIGGERING FROM LEADING OR
TRAILING EDGE
Q AND Q BUFFERED OUTPUT AVAILABLE
SEPARATE RESETS
WIDE RANGE OF OUTPUT PULSE WIDTHS
QUIESCENT CURRENT SPECIFIED UP TO
20V
5V, 10V AND 15V PARAMETRIC RATINGS
SCHMITT TRIGGER INPUT ALLOWS
UNLIMITED RISE AND FALL TIMES ON +TR
AND -TR INPUTS
INPUT LEAKAGE CURRENT
I
I
= 100nA (MAX) AT V
DD
= 18V T
A
= 25°C
100% TESTED FOR QUIESCENT CURRENT
MEETS ALL REQUIREMENTS OF JEDEC
JESD13B " STANDARD SPECIFICATIONS
FOR DESCRIPTION OF B SERIES CMOS
DEVICES"
DIP
SOP
ORDER CODES
PACKAGE
DIP
SOP
TUBE
HCF4538BEY
HCF4538BM1
T&R
HCF4538M013TR
DESCRIPTION
The HCF4538B is a monolithic integrated circuit
fabricated in Metal Oxide Semiconductor
technology available in DIP and SOP packages.
The HCF4538B dual precision monostable
multivibrator provides stable retriggerable/
resettable one-shot operation for any fixed voltage
PIN CONNECTION
timing application. An external resistor (R
X
) and
an external capacitor (C
X
) control the timing and
accuracy for the circuit. Adjustment of R
X
and C
X
provides a wide range of output pulse widths from
the Q and Q terminals. The time delay from trigger
input to output transition (trigger propagation
delay) and the time delay from reset input to
output transition (reset propagation delay) and the
time delay from reset input to output transition
(reset propagation delay) are independent of R
X
and C
X
. Precision control of output pulse width is
achieved through linear CMOS techniques.
Leading edge triggering (+TR) and trailing edge
triggering (-TR) inputs are provided for triggering
September 2001
1/10
HCF4538B
from either edge of an input pulse. An unused +TR
input should be tied to V
SS
. An unused -TR input
should be tied to V
DD
. A RESET (on low level) is
provided for immediate termination of the output
pulse or to prevent output pulses when power is
turned on. An unused RESET input should be tied
to V
DD
. However, if an entire section of the
HCF4538B is not used, its inputs must be tied to
either V
DD
or V
SS
(see table 1). In normal
operation the circuit triggers (extends the output
IINPUT EQUIVALENT CIRCUIT
pulse one period) on the application of each new
trigger pulse. For operation in the non-retiggerable
mode, Q is connected to -TR when leading edge
triggering (+TR) is used or Q is connected to +TR
when trailing edge triggering (-TR) is used. The
time period (T) for this multivibrator can be
calculated by : T = R
X
C
X
. The min. value of
external resistance, R
X
, is 4KΩ. The max. and
min. values of external capacitance, C
X
, are 100
µ
F and 5nF, respectively.
PIN DESCRIPTION
PIN No
4, 12
5, 11
3, 13
1, 15
2, 14
6, 10
7, 9
8
16
SYMBOL
+TR
-TR
RESET
C
X
1, C
X
2
R
X
C
X
1
R
X
C
X
2
Q1, Q2
Q1, Q2
V
SS
V
DD
NAME AND FUNCTION
Trigger Inputs (Low to
High, Edge-Triggered)
Trigger Inputs (High to
Low, Edge-Triggered)
Direct Reset Inputs
(Active Low)
External Capacitor Con-
nections
External Resistor/Capaci-
tor Connections
Pulse Outputs
Complementary Pulse
Outputs
Negative Supply Voltage
Positive Supply Voltage
Terminals 1, 8, 15 are electrically connected internally
FUNCTIONAL DIAGRAM
2/10
HCF4538B
TABLE 1 : Functional Terminal Connections
V
DD
to Term. N°
V
SS
to Term. N°
Input Pulse to
Term. N°
Other Connections
FUNCTION
Leading Edge Trigger/
Retriggerable
Leading Edge Trigger/Non
Retriggerable
Trailing Edge Trigger/
Retriggerable
Trailing Edge Trigger/Non
Retriggerable
Mono (1) Mono (2) Mono (1) Mono (2) Mono (1) Mono (2) Mono (1) Mono (2)
3, 5
3
3
3
11, 13
13
13
13
4
12
4
4
5
5
12
12
11
11
4, 6
12, 10
5, 7
11, 9
A Retriggerable one-shot multivibrator has an output pulse width which is extended on full time period (T) after application of the last trigger
pulse.
A Non-Retriggerable one-shot multivibrator has a time period (T) referenced from the application of the firs trigger pulse.
LOGIC DIAGRAM
3/10
HCF4538B
LOGIC DIAGRAM
ABSOLUTE MAXIMUM RATINGS
Symbol
V
DD
V
I
I
I
P
D
T
op
T
stg
Supply Voltage
DC Input Voltage
DC Input Current
Power Dissipation per Package
Power Dissipation per Output Transistor
Operating Temperature
Storage Temperature
Parameter
Value
-0.5 to +22
-0.5 to V
DD
+ 0.5
±
10
200
100
-55 to +125
-65 to +150
Unit
V
V
mA
mW
mW
°C
°C
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is
not implied.
All voltage values are referred to V
SS
pin voltage.
RECOMMENDED OPERATING CONDITIONS
Symbol
V
DD
V
I
T
op
Supply Voltage
Input Voltage
Operating Temperature
Parameter
Value
3 to 20
0 to V
DD
-55 to 125
Unit
V
V
°C
4/10
HCF4538B
DC SPECIFICATIONS
Test Condition
Symbol
Parameter
V
I
(V)
0/5
0/10
0/15
0/20
0/5
0/10
0/15
5/0
10/0
15/0
0.5/4.5
1/9
1.5/13.5
4.5/0.5
9/1
13.5/1.5
2.5
4.6
9.5
13.5
0.4
0.5
1.5
V
O
(V)
|I
O
| V
DD
(µA) (V)
5
10
15
20
5
10
15
5
10
15
5
10
15
5
10
15
5
5
10
15
5
10
15
18
T
A
= 25°C
Min.
Typ.
0.04
0.04
0.04
0.08
4.95
9.95
14.95
0.05
0.05
0.05
3.5
7
11
1.5
3
4
-1.6
-0.51
-1.3
-3.4
-0.51
-1.3
-3.4
-3.2
-1
-2.6
-6.8
1
2.6
6.8
±10
-5
5
±0.1
7.5
-1.3
-0.42
-1.1
-2.8
-0.42
-1.1
-2.8
±1
3.5
7
11
1.5
3
4
-1.3
-0.42
-1.1
-2.8
-0.42
-1.1
-2.8
±1
Max.
5
10
20
100
4.95
9.95
14.95
0.05
0.05
0.05
3.5
7
11
1.5
3
4
Value
-40 to 85°C
Min.
Max.
150
300
600
3000
4.95
9.95
14.95
0.05
0.05
0.05
-55 to 125°C
Min.
Max.
150
300
600
3000
Unit
I
L
Quiescent Current
µA
V
OH
High Level Output
Voltage
Low Level Output
Voltage
High Level Input
Voltage
Low Level Input
Voltage
Output Drive
Current
V
OL
V
IH
V
IL
I
OH
I
OL
Output Sink
Current
Input Leakage
Current
Input Capacitance
0/5
0/5
0/10
0/15
0/5
0/10
0/15
0/18
<1
<1
<1
<1
<1
<1
<1
<1
<1
<1
<1
<1
<1
<1
<1
<1
<1
<1
<1
V
V
V
V
mA
mA
µA
pF
I
I
C
I
Any Input
Any Input
The Noise Margin for both "1" and "0" level is: 1V min. with V
DD
=5V, 2V min. with V
DD
=10V, 2.5V min. with V
DD
=15V
5/10
