74HC4538; 74HCT4538
Dual retriggerable precision monostable multivibrator
Rev. 03 — 8 June 2009
Product data sheet
1. General description
The 74HC4538; 74HCT4538 are high-speed Si-gate CMOS devices and are pin
compatible with Low-power Schottky TTL (LSTTL). They are specified in compliance with
JEDEC standard no. 7A.
The 74HC4538; 74HCT4538 are dual retriggerable-resettable monostable multivibrators.
Each multivibrator has an active LOW trigger/retrigger input (nA), an active HIGH
trigger/retrigger input (nB), an overriding active LOW direct reset input (nCD), an output
(nQ) and its complement (nQ), and two pins (nREXT/CEXT and nCEXT) for connecting
the external timing components CEXT and REXT. Typical pulse width variation over the
specified temperature range is ±0.2 %.
The multivibrator may be triggered by either the positive or the negative edges of the input
pulse. The duration and accuracy of the output pulse are determined by the external
timing components CEXT and REXT. The output pulse width (tW) is equal to
0.7 × REXT × CEXT. The linear design techniques guarantee precise control of the output
pulse width. A LOW level at nCD terminates the output pulse immediately. Schmitt trigger
action on pins nA and nB makes the circuit highly tolerant of slower rise and fall times.
2. Features
n
n
n
n
n
Tolerant of slow trigger rise and fall times
Separate reset inputs
Triggering from falling or rising edge
Multiple package options
ESD protection:
u HBM JESD22-A114E exceeds 2000 V
u MM JESD22-A115-A exceeds 200 V
n Specified from −40 °C to +85 °C and from −40 °C to +125 °C
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
3. Ordering information
Table 1.
Ordering information
Type number
74HC4538N
Package
Temperature range
Name
Description
Version
−40 °C to +125 °C
DIP16
plastic dual in-line package; 16-leads (300 mil)
SOT38-4
−40 °C to +125 °C
SO16
plastic small outline package; 16 leads; body width 3.9 mm SOT109-1
−40 °C to +125 °C
SSOP16
plastic shrink small outline package; 16 leads;
body width 5.3 mm
−40 °C to +125 °C
TSSOP16 plastic thin shrink small outline package; 16 leads;
body width 4.4 mm
74HCT4538N
74HC4538D
74HCT4538D
74HC4538DB
74HCT4538DB
74HC4538PW
74HCT4538PW
SOT338-1
SOT403-1
4. Functional diagram
2
1REXT/CEXT
1
1CEXT
5
1A
4
1B
3
6
1Q
7
2Q
10
2Q
9
1CD
14
2REXT/CEXT
15
2CEXT
11
2A
12
2B
13
1Q
2CD
001aae727
Fig 1.
Functional diagram
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
2 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
nB
nA
VCC
nREXT/CEXT
Vref1
enable
nCEXT
GND
nCD
power-on reset
VCC
Vref2
enable
nQ
nQ
mba338
GND
Fig 2.
Logic diagram (one multivibrator)
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
3 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
5. Pinning information
5.1 Pinning
74HC4538
74HCT4538
1CEXT
1
16 VCC
1REXT/CEXT
2
15 2CEXT
1CD
3
14 2REXT/CEXT
74HC4538
74HCT4538
1CEXT
1
1REXT/CEXT
2
16 VCC
15 2CEXT
1B
4
13 2CD
1CD
3
14 2REXT/CEXT
1A
5
12 2B
1B
4
13 2CD
11 2A
1A
5
12 2B
1Q
6
11 2A
1Q
7
10 2Q
GND
8
1Q
1Q
GND
6
10 2Q
7
9
8
2Q
001aak190
Fig 3.
9
2Q
001aak191
Pin configuration for DIP16 and SO16
Fig 4.
Pin configuration for SSOP16 and TSSOP16
5.2 Pin description
Table 2.
Pin description
Symbol
Pin
Description
1CEXT, 2CEXT
1, 15
external capacitor connection (always connected to ground)
1REXT/CEXT, 2REXT/CEXT
2, 14
external capacitor/resistor connection
1CD, 2CD
3, 13
direct reset input (active LOW)
1B, 2B
4, 12
input (LOW to HIGH triggered)
1A, 2A
5, 11
input (HIGH to LOW triggered)
1Q, 2Q
6, 10
output
1Q, 2Q
7, 9
complementary output (active LOW)
GND
8
ground (0 V)
VCC
16
supply voltage
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
4 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
6. Functional description
Table 3.
Function table
Inputs
Outputs
nA
nB
nCD
↓
L
H
H
↑
H
X
X
L
[1]
nQ
nQ
L
H
H = HIGH voltage level; L = LOW voltage level; X = don’t care;
↑ = positive-going transition; ↓ = negative-going transition;
= one HIGH level output pulse, with the pule width determined by CEXT and REXT;
= one LOW level output pulse, with the pulse width determined by CEXT and REXT.
(1)
(1)
(2)
(1)
nB input
(3)
nA input
(4)
nCD input
nREXT/CEXT input
Vref2
Vref1
Vref1
Vref2
nQ output
T
T
T
(5)
001aae737
(1) Positive edge triggering.
(2) Positive edge re-triggering (pulse lengthening).
(3) Negative edge triggering.
(4) Reset (pulse shortening).
(5) T = 0.7 × REXT × CEXT (see also Figure 6).
Fig 5.
Timing diagram
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
5 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
CEXT
REXT
VCC
GND
nCEXT
nREXT/CEXT
nA
nB
nQ
T
nQ
T = 0.7 × REXT × CEXT
nCD
Fig 6.
001aak192
Connection of the external timing components REXT and CEXT
7. Limiting values
Table 4.
Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134). Voltages are referenced to GND (ground = 0 V).
Symbol
Parameter
VCC
supply voltage
Conditions
IIK
input clamping current
VI < −0.5 V or VI > VCC + 0.5 V
IOK
output clamping current
VO < −0.5 V or VO > VCC + 0.5 V
IO
output current
VO = −0.5 V to VCC + 0.5 V
ICC
supply current
IGND
ground current
Tstg
storage temperature
Ptot
total power dissipation
Min
Max
Unit
−0.5
+7.0
V
[1]
-
±20
mA
[1]
-
±20
mA
-
±25
mA
-
+50
mA
−50
-
mA
−65
+150
°C
Tamb = −40 °C to +125 °C
DIP16 package
[2]
-
750
mW
SO16 package
[3]
-
500
mW
(T)SSOP16 package
[4]
-
500
mW
[1]
The input and output voltage ratings may be exceeded if the input and output current ratings are observed.
[2]
Ptot derates linearly with 12 mW/K above 70 °C.
[3]
Ptot derates linearly with 8 mW/K above 70 °C.
[4]
Ptot derates linearly with 5.5 mW/K above 60 °C.
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
6 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
8. Recommended operating conditions
Table 5.
Recommended operating conditions
Voltages are referenced to GND (ground = 0 V)
Symbol Parameter
Conditions
74HC4538
Min
Typ
74HCT4538
Max
Min
Typ
Unit
Max
VCC
supply voltage
2.0
5.0
6.0
4.5
5.0
5.5
V
VI
input voltage
0
-
VCC
0
-
VCC
V
VO
output voltage
0
-
VCC
0
-
VCC
V
Tamb
ambient temperature
−40
-
+125
−40
-
+125
°C
∆t/∆V
input transition rise and fall rate
VCC = 2.0 V
-
-
625
-
-
-
ns/V
VCC = 4.5 V
-
1.67
139
-
1.67
139
ns/V
VCC = 6.0 V
-
-
83
-
-
-
ns/V
9. Static characteristics
Table 6.
Static characteristics
At recommended operating conditions; voltages are referenced to GND (ground = 0 V).
Symbol Parameter
25 °C
Conditions
−40 °C to +85 °C −40 °C to +125 °C Unit
Min
Typ
Max
Min
Max
Min
Max
74HC4538
VIH
VIL
VOH
VOL
II
HIGH-level
input voltage
VCC = 2.0 V
1.5
1.2
-
1.5
-
1.5
-
V
VCC = 4.5 V
3.15
2.4
-
3.15
-
3.15
-
V
VCC = 6.0 V
4.2
3.2
-
4.2
-
4.2
-
V
LOW-level
input voltage
VCC = 2.0 V
-
0.8
0.5
-
0.5
-
0.5
V
VCC = 4.5 V
-
2.1
1.35
-
1.35
-
1.35
V
VCC = 6.0 V
-
2.8
1.8
-
1.8
-
1.8
V
IO = −20 µA; VCC = 2.0 V
1.9
2.0
-
1.9
-
1.9
-
V
IO = −20 µA; VCC = 4.5 V
4.4
4.5
-
4.4
-
4.4
-
V
IO = −20 µA; VCC = 6.0 V
5.9
6.0
-
5.9
-
5.9
-
V
IO = −4.0 mA; VCC = 4.5 V
3.98
4.32
-
3.84
-
3.7
-
V
IO = −5.2 mA; VCC = 6.0 V
5.48
5.81
-
5.34
-
5.2
-
V
IO = 20 µA; VCC = 2.0 V
-
0
0.1
-
0.1
-
0.1
V
IO = 20 µA; VCC = 4.5 V
-
0
0.1
-
0.1
-
0.1
V
IO = 20 µA; VCC = 6.0 V
-
0
0.1
-
0.1
-
0.1
V
IO = 4.0 mA; VCC = 4.5 V
-
0.15
0.26
-
0.33
-
0.4
V
IO = 5.2 mA; VCC = 6.0 V
-
0.16
0.26
-
0.33
-
0.4
V
VI = VCC or GND;
VCC = 6.0 V
-
-
±0.1
-
±1
-
±1
µA
pin nREXT/CEXT;
VI = 2.0 V or GND; other
inputs at VCC or GND;
VCC = 6.0 V [1]
-
-
±0.5
-
±5
-
±10
µA
HIGH-level
output voltage
LOW-level
output voltage
input leakage
current
VI = VIH or VIL
VI = VIH or VIL
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
7 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
Table 6.
Static characteristics …continued
At recommended operating conditions; voltages are referenced to GND (ground = 0 V).
Symbol Parameter
ICC
supply current
CI
input
capacitance
25 °C
Conditions
VI = VCC or GND; IO = 0 A;
VCC = 6.0 V
−40 °C to +85 °C −40 °C to +125 °C Unit
Min
Typ
Max
Min
Max
Min
Max
-
-
8.0
-
80
-
160
µA
-
3.5
-
-
-
-
-
pF
74HCT4538
VIH
HIGH-level
input voltage
VCC = 4.5 V to 5.5 V
2.0
1.6
-
2.0
-
2.0
-
V
VIL
LOW-level
input voltage
VCC = 4.5 V to 5.5 V
-
1.2
0.8
-
0.8
-
0.8
V
VOH
HIGH-level
output voltage
VI = VIH or VIL; VCC = 4.5 V
IO = −20 µA
4.4
4.5
-
4.4
-
4.4
-
V
IO = −4.0 mA
3.98
4.32
-
3.84
-
3.7
-
V
LOW-level
output voltage
VOL
input leakage
current
II
VI = VIH or VIL; VCC = 4.5 V
IO = 20 µA; VCC = 4.5 V
-
0
0.1
-
0.1
-
0.1
V
IO = 4.0 mA; VCC = 4.5 V
-
0.15
0.26
-
0.33
-
0.4
V
VI = VCC or GND;
VCC = 5.5 V
-
-
±0.1
-
±1
-
±1
µA
pin nREXT/CEXT;
VI = 2.0 V or GND; other
inputs at VCC or GND;
VCC = 5.5 V [1]
-
-
±0.5
-
±5
-
±10
µA
-
-
8.0
-
80
-
160
µA
pin nA, nB
-
50
180
-
225
-
245
µA
pin nCD
-
65
234
-
293
-
319
µA
-
3.5
-
-
-
-
-
pF
ICC
supply current
VI = VCC or GND; IO = 0 A;
VCC = 5.5 V
∆ICC
additional
supply current
VI = VCC − 2.1 V; IO = 0 A;
other inputs at VCC or GND;
VCC = 4.5 V to 5.5 V
CI
[1]
input
capacitance
This measurement can only be carried out after a trigger pulse is applied.
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
8 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
10. Dynamic characteristics
Table 7.
Dynamic characteristics
Voltages are referenced to GND (ground = 0 V); for test circuit see Figure 9.
Symbol Parameter
25 °C
Conditions
−40 °C to
+85 °C
−40 °C to
+125 °C
Min
Typ[1]
Max
Min
Max
Min
Max
Unit
74HC4538
tPLH
LOW to HIGH
propagation
delay
nA, nB to nQ;
see Figure 7
VCC = 2.0 V
-
85
265
-
330
-
400
ns
VCC = 4.5 V
-
31
53
-
66
-
80
ns
VCC = 5.0 V; CL = 15 pF
-
27
-
-
-
-
-
ns
VCC = 6.0 V
-
25
45
-
56
-
68
ns
VCC = 2.0 V
-
83
265
-
340
-
400
ns
VCC = 4.5 V
-
30
53
-
68
-
80
ns
VCC = 6.0 V
-
24
45
-
58
-
68
ns
VCC = 2.0 V
-
83
265
-
330
-
400
ns
VCC = 4.5 V
-
30
53
-
66
-
80
ns
VCC = 5.0 V; CL = 15 pF
-
27
-
-
-
-
-
ns
VCC = 6.0 V
-
24
45
-
56
-
68
ns
VCC = 2.0 V
-
80
265
-
330
-
400
ns
VCC = 4.5 V
-
29
53
-
66
-
80
ns
VCC = 6.0 V
-
23
45
-
56
-
68
ns
VCC = 2.0 V
-
19
75
-
95
-
119
ns
VCC = 4.5 V
-
7
15
-
19
-
22
ns
VCC = 6.0 V
-
6
13
-
16
-
19
ns
nCD to nQ; see Figure 7
tPHL
HIGH to LOW
propagation
delay
nA, nB to nQ;
see Figure 7
nCD to nQ; see Figure 7
tt
transition time
nQ and nQ; see Figure 7
[2]
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
9 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
Table 7.
Dynamic characteristics …continued
Voltages are referenced to GND (ground = 0 V); for test circuit see Figure 9.
Symbol Parameter
tW
pulse width
25 °C
Conditions
−40 °C to
+85 °C
−40 °C to
+125 °C
Unit
Min
Typ[1]
Max
Min
Max
Min
Max
VCC = 2.0 V
80
17
-
100
-
120
-
ns
VCC = 4.5 V
16
6
-
20
-
24
-
ns
VCC = 6.0 V
14
5
-
17
-
20
-
ns
VCC = 2.0 V
80
17
-
100
-
120
-
ns
VCC = 4.5 V
16
6
-
20
-
24
-
ns
VCC = 6.0 V
14
5
-
17
-
20
-
ns
VCC = 2.0 V
80
19
-
100
-
120
-
ns
VCC = 4.5 V
16
7
-
20
-
24
-
ns
VCC = 6.0 V
14
6
-
17
-
20
-
ns
630
700
770
602
798
595
805
µs
VCC = 2.0 V
35
6
-
45
-
55
-
ns
VCC = 4.5 V
7
2
-
9
-
11
-
ns
VCC = 6.0 V
6
2
-
8
-
9
-
ns
VCC = 2.0 V
-
455 + X
-
-
-
-
-
ns
VCC = 4.5 V
-
80 + X
-
-
-
-
-
ns
VCC = 6.0 V
-
55 + X
-
-
-
-
-
ns
VCC = 2.0 V
10
-
1000
-
-
-
-
kΩ
VCC = 5.0 V
2
-
1000
-
-
-
-
kΩ
-
-
-
pF
nA LOW; see Figure 8
nB HIGH; see Figure 8
nCD LOW; see Figure 8
nQ and nQ HIGH or LOW;
see Figure 8
VCC = 5.0 V;
CEXT = 0.1 µF;
REXT = 10 kΩ
trec
trtrig
recovery time
retrigger time
REXT
external timing
resistor
CEXT
external timing
capacitor
CPD
power
dissipation
capacitance
nCD to nA, nB;
see Figure 8
nA, nB; see Figure 8;
X = CEXT / (4.5 × VCC)
no limits
per multivibrator;
VI = GND to VCC
[3]
-
136
74HC_HCT4538_3
Product data sheet
-
-
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
10 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
Table 7.
Dynamic characteristics …continued
Voltages are referenced to GND (ground = 0 V); for test circuit see Figure 9.
Symbol Parameter
25 °C
Conditions
−40 °C to
+85 °C
−40 °C to
+125 °C
Unit
Min
Typ[1]
Max
Min
Max
Min
Max
VCC = 4.5 V
-
35
60
-
75
-
90
ns
VCC = 5.0 V; CL = 15 pF
-
30
-
-
-
-
-
ns
-
35
60
-
75
-
90
ns
VCC = 4.5 V
-
35
60
-
75
-
90
ns
VCC = 5.0 V; CL = 15 pF
-
30
-
-
-
-
-
ns
-
35
60
-
75
-
90
ns
-
7
15
-
19
-
21
ns
20
11
-
25
-
30
-
ns
16
5
-
20
-
24
-
ns
20
11
-
25
-
30
-
ns
630
700
770
602
798
595
805
µs
7
2
-
9
-
11
-
ns
VCC = 4.5 V
-
80 + X
-
-
-
-
-
ns
2
-
1000
-
-
-
-
kΩ
74HCT4538
tPLH
LOW to HIGH
propagation
delay
nA, nB to nQ;
see Figure 7
nCD to nQ; see Figure 7
VCC = 4.5 V
tPHL
HIGH to LOW
propagation
delay
nA, nB to nQ;
see Figure 7
nCD to nQ; see Figure 7
VCC = 4.5 V
tt
transition time
nQ and nQ; see Figure 7
VCC = 4.5 V
tW
pulse width
[2]
nA LOW; see Figure 8
VCC = 4.5 V
nB HIGH; see Figure 8
VCC = 4.5 V
nCD LOW; see Figure 8
VCC = 4.5 V
nQ and nQ HIGH or LOW;
see Figure 8
VCC = 5.0 V;
CEXT = 0.1 µF;
REXT = 10 kΩ
trec
recovery time
nCD to nA, nB;
see Figure 8
trtrig
retrigger time
nA, nB; see Figure 8;
X = CEXT / (4.5 × VCC)
VCC = 4.5 V
REXT
external timing
resistor
VCC = 5.0 V
CEXT
external timing
capacitor
VCC = 5.0 V
no limits
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
11 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
Table 7.
Dynamic characteristics …continued
Voltages are referenced to GND (ground = 0 V); for test circuit see Figure 9.
Symbol Parameter
CPD
25 °C
Conditions
power
dissipation
capacitance
per multivibrator;
VI = GND to (VCC − 1.5 V)
[3]
−40 °C to
+85 °C
−40 °C to
+125 °C
Min
Typ[1]
Max
Min
Max
Min
Max
-
138
-
-
-
-
-
[1]
Typical values are measured at nominal supply voltage (VCC = 3.3 V and VCC = 5.0 V).
[2]
tt is the same as tTHL and tTLH.
[3]
CPD is used to determine the dynamic power dissipation (PD in µW).
PD = CPD × VCC2 × fi × Σ(CL × VCC2 × fo) + 0.48 × CEXT × VCC2 × fo + D × 0.8 × VCC where:
fi = input frequency in MHz;
fo = output frequency in MHz;
Σ(CL × VCC2 × fo) = sum of the outputs;
CL = output load capacitance in pF;
VCC = supply voltage in V;
D = duty cycle factor in %;
CEXT = external timing capacitance in pF.
Unit
pF
11. Waveforms
VI
nB input
GND
VM
tW
VI
nA input
VM
GND
tW
VI
nCD input
GND
VM
tPLH
VOH
nQ output
VM
VOL
tPHL
tPLH
VY
VX
tTHL
tPHL
VM
tPHL
tTLH
VOH
nQ output
tPLH
VY
VM
VX
VOL
001aak194
Measurement points are given in Table 8.
Logic levels: VOL and VOH are typical output levels that occur with the output load.
Fig 7.
Waveforms showing propagation delays and transition times
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
12 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
VI
nCD input
VM
GND
trec
tW
tW
VI
nA input
VM
GND
tW
VI
nB input
VM
GND
trtrig
VOH
VM
nQ, nQ output
VOL
tW
001aak195
Measurement points are given in Table 8.
Logic levels: VOL and VOH are typical output levels that occur with the output load.
Fig 8.
Waveforms showing nA, nB, nQ, nQ pulse widths, recovery and retrigger times
Table 8.
Measurement points
Type
Input
Output
VM
VM
VX
VY
74HC4538
0.5VCC
0.5VCC
0.1VCC
0.9VCC
74HCT4538
1.3 V
1.3 V
0.1VCC
0.9VCC
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
13 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
VI
tW
90 %
negative
pulse
VM
0V
tf
tr
tr
tf
VI
90 %
positive
pulse
0V
VM
10 %
VM
VM
10 %
tW
VCC
VCC
G
VI
VO
RL
S1
open
DUT
RT
CL
001aad983
Test data is given in Table 9.
Definitions test circuit:
RT = Termination resistance should be equal to output impedance Zo of the pulse generator.
CL = Load capacitance including jig and probe capacitance.
RL = Load resistance.
S1 = Test selection switch
Fig 9.
Test circuit for measuring switching times
Table 9.
Test data
Type
Input
Load
S1 position
VI
tr, tf
CL
RL
tPHL, tPLH
74HC4538
VCC
6 ns
15 pF, 50 pF
1 kΩ
open
74HCT4538
3V
6 ns
15 pF, 50 pF
1 kΩ
open
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
14 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
12. Application information
12.1 Power-down considerations
A large capacitor (CEXT) may cause problems when powering-down the monostable due
to energy stored in this capacitor. When a system containing this device is powered-down
or rapid decrease of VCC to zero occurs, the monostable may sustain damage, due to the
capacitor discharging through the input protection diodes. To avoid this possibility, use a
damping diode (DEXT) preferably a germanium or Schottky type diode able to withstand
large current surges and connect as shown in Figure 10
DEXT
CEXT
REXT
VCC
GND
nCEXT
nREXT/CEXT
001aak193
Fig 10. Power-down protection circuit
12.2 Graphs
001aak196
1.6
1 kΩ
2 kΩ
5.6 kΩ
51 kΩ
1 MΩ
normalized
K factor
(K)
1.12
REXT ×
CEXT
(tW)
1.2
0.84
1.0
0.70
0.8
0.56
0.6
10−10
10−9
10−8
10−7
10−6
0.42
10−4
10−5
CEXT (F)
VCC = 4.5 V; Tamb = 25 °C.
Fig 11. Typical pulse width accuracy versus external capacitance
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
15 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
001aak197
1.6
1.12
REXT ×
CEXT
(tW)
normalized
K factor
(K)
1.2
0.84
1 nF
1.0
0.70
> 100 nF
0.8
0.56
0.6
103
104
0.42
106
105
REXT (Ω)
VCC = 4.5 V; Tamb = 25 °C.
Fig 12. Typical pulse width accuracy versus external resistance
001aak198
1.6
1.12
REXT ×
CEXT
(tW)
normalized
K factor
(K)
1.2
0.84
+10 %
REXT
1.0
0.70
−10 %
0.8
0.56
0.6
10−10
10−9
10−8
10−7
10−6
0.42
10−4
10−5
CEXT (F)
VCC = 4.5 V; REXT = 10 kΩ; Tamb = 25 °C.
Fig 13. Typical pulse width accuracy versus external capacitance
001aak199
1.7
normalized
K factor
(K)
2 kΩ
1 kΩ
1.19
REXT ×
CEXT
(tW)
5.6 kΩ
1.3
0.91
10 kΩ
1.1
0.77
1 MΩ
0.9
0.63
0.7
0.49
1
2
3
4
5
6
VCC (V)
CEXT = 1 nF; Tamb = 25 °C.
Fig 14. Typical pulse width accuracy versus power supply
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
16 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
001aak200
1.7
1.19
REXT ×
CEXT
(tW)
normalized
K factor
(K)
1 kΩ
1.3
0.91
2 kΩ
5.6 kΩ
1 MΩ
1.1
0.77
0.9
0.63
0.7
0.49
1
2
3
4
5
6
VCC (V)
CEXT = 100 nF; Tamb = 25 °C.
Fig 15. Typical pulse width accuracy versus power supply
001aak201
1.7
REXT ×
CEXT
(tW)
1 kΩ
normalized
K factor
(K)
2 kΩ
1.3
1.19
0.91
5.6 kΩ
1.1
0.77
1 MΩ
0.9
0.7
−50
0.63
0
50
0.49
150
100
Tamb (°C)
VCC = 4.5 V; CEXT = 1 nF; Tamb = 25 °C.
Fig 16. Typical pulse width accuracy versus temperature
001aak202
1.7
1.19
REXT ×
CEXT
(tW)
normalized
K factor
(K)
1.3
0.91
1.1
0.77
1 kΩ
2 kΩ
5.6 kΩ
1 MΩ
0.9
0.7
−50
0
50
0.63
0.49
150
100
Tamb (°C)
VCC = 4.5 V; CEXT = 1 µF; Tamb = 25 °C.
Fig 17. Typical pulse width accuracy versus temperature
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
17 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
13. Package outline
DIP16: plastic dual in-line package; 16 leads (300 mil)
SOT38-4
ME
seating plane
D
A2
A
A1
L
c
e
Z
w M
b1
(e 1)
b
b2
MH
9
16
pin 1 index
E
1
8
0
5
10 mm
scale
DIMENSIONS (inch dimensions are derived from the original mm dimensions)
UNIT
A
max.
A1
min.
A2
max.
b
b1
b2
c
D (1)
E (1)
e
e1
L
ME
MH
w
Z (1)
max.
mm
4.2
0.51
3.2
1.73
1.30
0.53
0.38
1.25
0.85
0.36
0.23
19.50
18.55
6.48
6.20
2.54
7.62
3.60
3.05
8.25
7.80
10.0
8.3
0.254
0.76
inches
0.17
0.02
0.13
0.068
0.051
0.021
0.015
0.049
0.033
0.014
0.009
0.77
0.73
0.26
0.24
0.1
0.3
0.14
0.12
0.32
0.31
0.39
0.33
0.01
0.03
Note
1. Plastic or metal protrusions of 0.25 mm (0.01 inch) maximum per side are not included.
OUTLINE
VERSION
REFERENCES
IEC
JEDEC
JEITA
EUROPEAN
PROJECTION
ISSUE DATE
95-01-14
03-02-13
SOT38-4
Fig 18. Package outline SOT38-4 (DIP16)
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
18 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
SO16: plastic small outline package; 16 leads; body width 3.9 mm
SOT109-1
D
E
A
X
c
y
HE
v M A
Z
16
9
Q
A2
A
(A 3)
A1
pin 1 index
θ
Lp
1
L
8
e
0
detail X
w M
bp
2.5
5 mm
scale
DIMENSIONS (inch dimensions are derived from the original mm dimensions)
UNIT
A
max.
A1
A2
A3
bp
c
D (1)
E (1)
e
HE
L
Lp
Q
v
w
y
Z (1)
mm
1.75
0.25
0.10
1.45
1.25
0.25
0.49
0.36
0.25
0.19
10.0
9.8
4.0
3.8
1.27
6.2
5.8
1.05
1.0
0.4
0.7
0.6
0.25
0.25
0.1
0.7
0.3
0.01
0.019 0.0100 0.39
0.014 0.0075 0.38
0.039
0.016
0.028
0.020
inches
0.010 0.057
0.069
0.004 0.049
0.16
0.15
0.05
0.244
0.041
0.228
0.01
0.01
0.028
0.004
0.012
θ
o
8
o
0
Note
1. Plastic or metal protrusions of 0.15 mm (0.006 inch) maximum per side are not included.
REFERENCES
OUTLINE
VERSION
IEC
JEDEC
SOT109-1
076E07
MS-012
JEITA
EUROPEAN
PROJECTION
ISSUE DATE
99-12-27
03-02-19
Fig 19. Package outline SOT109-1 (SO16)
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
19 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
SSOP16: plastic shrink small outline package; 16 leads; body width 5.3 mm
D
SOT338-1
E
A
X
c
y
HE
v M A
Z
9
16
Q
A2
A
(A 3)
A1
pin 1 index
θ
Lp
L
8
1
detail X
w M
bp
e
0
2.5
5 mm
scale
DIMENSIONS (mm are the original dimensions)
UNIT
A
max.
A1
A2
A3
bp
c
D (1)
E (1)
e
HE
L
Lp
Q
v
w
y
Z (1)
θ
mm
2
0.21
0.05
1.80
1.65
0.25
0.38
0.25
0.20
0.09
6.4
6.0
5.4
5.2
0.65
7.9
7.6
1.25
1.03
0.63
0.9
0.7
0.2
0.13
0.1
1.00
0.55
8
o
0
o
Note
1. Plastic or metal protrusions of 0.25 mm maximum per side are not included.
OUTLINE
VERSION
SOT338-1
REFERENCES
IEC
JEDEC
JEITA
EUROPEAN
PROJECTION
ISSUE DATE
99-12-27
03-02-19
MO-150
Fig 20. Package outline SOT338-1 (SSOP16)
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
20 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
TSSOP16: plastic thin shrink small outline package; 16 leads; body width 4.4 mm
SOT403-1
E
D
A
X
c
y
HE
v M A
Z
9
16
Q
(A 3)
A2
A
A1
pin 1 index
θ
Lp
L
1
8
e
detail X
w M
bp
0
2.5
5 mm
scale
DIMENSIONS (mm are the original dimensions)
UNIT
A
max.
A1
A2
A3
bp
c
D (1)
E (2)
e
HE
L
Lp
Q
v
w
y
Z (1)
θ
mm
1.1
0.15
0.05
0.95
0.80
0.25
0.30
0.19
0.2
0.1
5.1
4.9
4.5
4.3
0.65
6.6
6.2
1
0.75
0.50
0.4
0.3
0.2
0.13
0.1
0.40
0.06
8
o
0
o
Notes
1. Plastic or metal protrusions of 0.15 mm maximum per side are not included.
2. Plastic interlead protrusions of 0.25 mm maximum per side are not included.
OUTLINE
VERSION
SOT403-1
REFERENCES
IEC
JEDEC
JEITA
EUROPEAN
PROJECTION
ISSUE DATE
99-12-27
03-02-18
MO-153
Fig 21. Package outline SOT403-1 (TSSOP16)
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
21 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
14. Abbreviations
Table 10.
Abbreviations
Acronym
Description
CMOS
Complementary Metal-Oxide Semiconductor
DUT
Device Under Test
ESD
ElectroStatic Discharge
HBM
Human Body Model
LSTTL
Low-power Schottky Transistor-Transistor Logic
MM
Machine Model
TTL
Transistor-Transistor Logic
15. Revision history
Table 11.
Revision history
Document ID
Release date
Data sheet status
Change notice
Supersedes
74HC_HCT4538_3
20090608
Product data sheet
-
74HC_HCT4538_CNV_2
Modifications:
74HC_HCT4538_CNV_2
•
The format of this data sheet has been redesigned to comply with the new identity
guidelines of NXP Semiconductors.
•
•
•
Legal texts have been adapted to the new company name where appropriate.
•
•
•
Test circuit added: Figure 9.
Pin names changed throughout.
Section Section 7, Section 8 and Section 9 added, taken from the 74HC/T HCMOS Family
characteristics/specification (March 1988).
Quick reference data incorporated in to Section 9 and Section 10.
Package information added for DIP16, SO16, SSOP16 and TSSOP16 packages.
19970902
Product specification
74HC_HCT4538_3
Product data sheet
-
-
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
22 of 24
74HC4538; 74HCT4538
NXP Semiconductors
Dual retriggerable precision monostable multivibrator
16. Legal information
16.1 Data sheet status
Document status[1][2]
Product status[3]
Definition
Objective [short] data sheet
Development
This document contains data from the objective specification for product development.
Preliminary [short] data sheet
Qualification
This document contains data from the preliminary specification.
Product [short] data sheet
Production
This document contains the product specification.
[1]
Please consult the most recently issued document before initiating or completing a design.
[2]
The term ‘short data sheet’ is explained in section “Definitions”.
[3]
The product status of device(s) described in this document may have changed since this document was published and may differ in case of multiple devices. The latest product status
information is available on the Internet at URL http://www.nxp.com.
16.2 Definitions
Draft — The document is a draft version only. The content is still under
internal review and subject to formal approval, which may result in
modifications or additions. NXP Semiconductors does not give any
representations or warranties as to the accuracy or completeness of
information included herein and shall have no liability for the consequences of
use of such information.
Short data sheet — A short data sheet is an extract from a full data sheet
with the same product type number(s) and title. A short data sheet is intended
for quick reference only and should not be relied upon to contain detailed and
full information. For detailed and full information see the relevant full data
sheet, which is available on request via the local NXP Semiconductors sales
office. In case of any inconsistency or conflict with the short data sheet, the
full data sheet shall prevail.
16.3 Disclaimers
General — Information in this document is believed to be accurate and
reliable. However, NXP Semiconductors does not give any representations or
warranties, expressed or implied, as to the accuracy or completeness of such
information and shall have no liability for the consequences of use of such
information.
Right to make changes — NXP Semiconductors reserves the right to make
changes to information published in this document, including without
limitation specifications and product descriptions, at any time and without
notice. This document supersedes and replaces all information supplied prior
to the publication hereof.
Suitability for use — NXP Semiconductors products are not designed,
authorized or warranted to be suitable for use in medical, military, aircraft,
space or life support equipment, nor in applications where failure or
malfunction of an NXP Semiconductors product can reasonably be expected
to result in personal injury, death or severe property or environmental
damage. NXP Semiconductors accepts no liability for inclusion and/or use of
NXP Semiconductors products in such equipment or applications and
therefore such inclusion and/or use is at the customer’s own risk.
Applications — Applications that are described herein for any of these
products are for illustrative purposes only. NXP Semiconductors makes no
representation or warranty that such applications will be suitable for the
specified use without further testing or modification.
Limiting values — Stress above one or more limiting values (as defined in
the Absolute Maximum Ratings System of IEC 60134) may cause permanent
damage to the device. Limiting values are stress ratings only and operation of
the device at these or any other conditions above those given in the
Characteristics sections of this document is not implied. Exposure to limiting
values for extended periods may affect device reliability.
Terms and conditions of sale — NXP Semiconductors products are sold
subject to the general terms and conditions of commercial sale, as published
at http://www.nxp.com/profile/terms, including those pertaining to warranty,
intellectual property rights infringement and limitation of liability, unless
explicitly otherwise agreed to in writing by NXP Semiconductors. In case of
any inconsistency or conflict between information in this document and such
terms and conditions, the latter will prevail.
No offer to sell or license — Nothing in this document may be interpreted
or construed as an offer to sell products that is open for acceptance or the
grant, conveyance or implication of any license under any copyrights, patents
or other industrial or intellectual property rights.
Export control — This document as well as the item(s) described herein
may be subject to export control regulations. Export might require a prior
authorization from national authorities.
16.4 Trademarks
Notice: All referenced brands, product names, service names and trademarks
are the property of their respective owners.
17. Contact information
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: salesaddresses@nxp.com
74HC_HCT4538_3
Product data sheet
© NXP B.V. 2009. All rights reserved.
Rev. 03 — 8 June 2009
23 of 24
NXP Semiconductors
74HC4538; 74HCT4538
Dual retriggerable precision monostable multivibrator
18. Contents
1
2
3
4
5
5.1
5.2
6
7
8
9
10
11
12
12.1
12.2
13
14
15
16
16.1
16.2
16.3
16.4
17
18
General description . . . . . . . . . . . . . . . . . . . . . . 1
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Ordering information . . . . . . . . . . . . . . . . . . . . . 2
Functional diagram . . . . . . . . . . . . . . . . . . . . . . 2
Pinning information . . . . . . . . . . . . . . . . . . . . . . 4
Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 4
Functional description . . . . . . . . . . . . . . . . . . . 5
Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . . 6
Recommended operating conditions. . . . . . . . 7
Static characteristics. . . . . . . . . . . . . . . . . . . . . 7
Dynamic characteristics . . . . . . . . . . . . . . . . . . 9
Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Application information. . . . . . . . . . . . . . . . . . 15
Power-down considerations . . . . . . . . . . . . . . 15
Graphs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Package outline . . . . . . . . . . . . . . . . . . . . . . . . 18
Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Revision history . . . . . . . . . . . . . . . . . . . . . . . . 22
Legal information. . . . . . . . . . . . . . . . . . . . . . . 23
Data sheet status . . . . . . . . . . . . . . . . . . . . . . 23
Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Contact information. . . . . . . . . . . . . . . . . . . . . 23
Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Please be aware that important notices concerning this document and the product(s)
described herein, have been included in section ‘Legal information’.
© NXP B.V. 2009.
All rights reserved.
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: salesaddresses@nxp.com
Date of release: 8 June 2009
Document identifier: 74HC_HCT4538_3