1/10
September 2001
s
RETRIGGERABLE/RESETTABLE
CAPABILITY
s
TRIGGER AND RESET PROPAGATION
DELAYS INDEPENDENT OF R
X
, C
X
s
TRIGGERING FROM LEADING OR
TRAILING EDGE
s
Q AND Q BUFFERED OUTPUT AVAILABLE
s
SEPARATE RESETS
s
WIDE RANGE OF OUTPUT PULSE WIDTHS
s
QUIESCENT CURRENT SPECIFIED UP TO
20V
s
5V, 10V AND 15V PARAMETRIC RATINGS
s
SCHMITT TRIGGER INPUT ALLOWS
UNLIMITED RISE AND FALL TIMES ON +TR
AND -TR INPUTS
s
INPUT LEAKAGE CURRENT
I
I
= 100nA (MAX) AT V
DD
= 18V T
A
= 25C
s
100% TESTED FOR QUIESCENT CURRENT
s
MEETS ALL REQUIREMENTS OF JEDEC
JESD13B " STANDARD SPECIFICATIONS
FOR DESCRIPTION OF B SERIES CMOS
DEVICES"
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
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
HCF4538B
DUAL MONOSTABLE MULTIVIBRATOR
PIN CONNECTION
ORDER CODES
PACKAGE
TUBE
T & R
DIP
HCF4538BEY
SOP
HCF4538BM1
HCF4538M013TR
DIP
SOP
HCF4538B
2/10
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
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 4K
.
The max. and
min. values of external capacitance, C
X
, are 100
F and 5nF, respectively.
IINPUT EQUIVALENT CIRCUIT
PIN DESCRIPTION
Terminals 1, 8, 15 are electrically connected internally
FUNCTIONAL DIAGRAM
PIN No
SYMBOL
NAME AND FUNCTION
4, 12
+TR
Trigger Inputs (Low to
High, Edge-Triggered)
5, 11
-TR
Trigger Inputs (High to
Low, Edge-Triggered)
3, 13
RESET
Direct Reset Inputs
(Active Low)
1, 15
C
X
1, C
X
2
External Capacitor Con-
nections
2, 14
R
X
C
X
1
R
X
C
X
2
External Resistor/Capaci-
tor Connections
6, 10
Q1, Q2
Pulse Outputs
7, 9
Q1, Q2
Complementary Pulse
Outputs
8
V
SS
Negative Supply Voltage
16
V
DD
Positive Supply Voltage
HCF4538B
3/10
TABLE 1 : Functional Terminal Connections
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
FUNCTION
V
DD
to Term. N
V
SS
to Term. N
Input Pulse to
Term. N
Other Connections
Mono (1) Mono (2) Mono (1) Mono (2) Mono (1) Mono (2) Mono (1) Mono (2)
Leading Edge Trigger/
Retriggerable
3, 5
11, 13
4
12
Leading Edge Trigger/Non
Retriggerable
3
13
4
12
5, 7
11, 9
Trailing Edge Trigger/
Retriggerable
3
13
4
12
5
11
Trailing Edge Trigger/Non
Retriggerable
3
13
5
11
4, 6
12, 10
HCF4538B
4/10
LOGIC DIAGRAM
ABSOLUTE MAXIMUM RATINGS
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
Parameter
Value
Unit
V
DD
Supply Voltage
-0.5 to +22
V
V
I
DC Input Voltage
-0.5 to V
DD
+ 0.5
V
I
I
DC Input Current
10
mA
P
D
Power Dissipation per Package
200
mW
Power Dissipation per Output Transistor
100
mW
T
op
Operating Temperature
-55 to +125
C
T
stg
Storage Temperature
-65 to +150
C
Symbol
Parameter
Value
Unit
V
DD
Supply Voltage
3 to 20
V
V
I
Input Voltage
0 to V
DD
V
T
op
Operating Temperature
-55 to 125
C
HCF4538B
5/10
DC SPECIFICATIONS
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
Symbol
Parameter
Test Condition
Value
Unit
V
I
(V)
V
O
(V)
|I
O
|
(
A)
V
DD
(V)
T
A
= 25C
-40 to 85C
-55 to 125C
Min.
Typ.
Max.
Min.
Max.
Min.
Max.
I
L
Quiescent Current
0/5
5
0.04
5
150
150
A
0/10
10
0.04
10
300
300
0/15
15
0.04
20
600
600
0/20
20
0.08
100
3000
3000
V
OH
High Level Output
Voltage
0/5
<1
5
4.95
4.95
4.95
V
0/10
<1
10
9.95
9.95
9.95
0/15
<1
15
14.95
14.95
14.95
V
OL
Low Level Output
Voltage
5/0
<1
5
0.05
0.05
0.05
V
10/0
<1
10
0.05
0.05
0.05
15/0
<1
15
0.05
0.05
0.05
V
IH
High Level Input
Voltage
0.5/4.5
<1
5
3.5
3.5
3.5
V
1/9
<1
10
7
7
7
1.5/13.5
<1
15
11
11
11
V
IL
Low Level Input
Voltage
4.5/0.5
<1
5
1.5
1.5
1.5
V
9/1
<1
10
3
3
3
13.5/1.5
<1
15
4
4
4
I
OH
Output Drive
Current
0/5
2.5
<1
5
-1.6
-3.2
-1.3
-1.3
mA
0/5
4.6
<1
5
-0.51
-1
-0.42
-0.42
0/10
9.5
<1
10
-1.3
-2.6
-1.1
-1.1
0/15
13.5
<1
15
-3.4
-6.8
-2.8
-2.8
I
OL
Output Sink
Current
0/5
0.4
<1
5
-0.51
1
-0.42
-0.42
mA
0/10
0.5
<1
10
-1.3
2.6
-1.1
-1.1
0/15
1.5
<1
15
-3.4
6.8
-2.8
-2.8
I
I
Input Leakage
Current
0/18
Any Input
18
10
-5
0.1
1
1
A
C
I
Input Capacitance
Any Input
5
7.5
pF
PDF 
ZIP