1. General description
74HC423; 74HCT423 are high-spee d Si-gate CMOS devices that ar e pin comp atible with
Low power Schottky TTL (LSTTL). They are specified in compliance with JEDEC
standard no. 7A.
The 74HC423; 74HCT423 dual retriggerable monostable multivibrator with reset has two
methods of output pulse width control.
1. The minimum pulse width is essentially determined by the selection of an external
resistor (REXT) and capacitor (CEXT), see Section 12.1.
2. Once triggered, the basic output pulse width may be extended by retriggering the
gated active LOW- going edge input (nA) or the active HIGH-going edge in put (nB). By
repeating this process, the ou tput pulse peri od (nQ = HIGH, n Q = LOW) can be made
as long as desired. When nRD is LOW, it forces the nQ output LOW, the nQ output
HIGH and also inhibits the triggering. Figure 10 and Figure 11 illustrate pulse control
by reset.
The nA and nB inputs’ Schmitt trigger action makes them highly tolerant to slower input
rise and fall times.
The 74HC423; 74HCT423 are identical to the 74HC123; 74HCT123 except that they
cannot be triggered via the reset input.
2. Features and benefits
DC triggered from active HIGH or active LOW inputs
Retriggerable for very long pulses up to 100 % duty factor
Direct reset termin ate s ou tp ut puls e
Schmitt-trigger action on all inputs except for the reset input
Complies with JEDEC standard no. 7A
ESD protection:
HBM JESD22-A114F exceeds 2000 V
MM JESD22-A115-A exceeds 200 V
Specified from 40 Cto+85C and from 40 Cto+125C
74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
Rev. 6 — 19 December 2011 Product data sheet
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 2 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
3. Ordering information
4. Functional diagram
Table 1. Ordering information
Type number Package
Temperature ran ge Name Description Version
74HC423N 40 C to +125 C DIP16 plastic dual in-line package; 16 leads (300 mil) SOT38-4
74HCT423N
74HC423D 40 C to +125 C SO16 plastic small outline package; 16 leads;
body width 3.9 mm SOT109-1
74HCT423D
74HC423BQ 40 C to +125 C DHVQFN16 plastic dual in-line compatible thermal enhanced very thin
quad flat package; no leads; 16 terminals;
body 2.5 3.5 0.85 mm
SOT763-1
74HCT423BQ
74HCT423DB 40 C to +125 C SSOP16 plastic shrink small outline package; 16 leads;
body width 5.3 mm SOT338-1
74HCT423PW 40 C to +125 C TSSOP16 plastic thin shrink small outline package; 16 leads;
body width 4.4 mm SOT403-1
Fig 1. Functional Diagram
1Q
Q
S13
1REXT/CEXT
15
1CEXT
14
1Q
Q4
9
001aah796
2A
1
1A
10
2B
2
1B
3
1RD
T
RD
Q
S
2REXT/CEXT
7
2CEXT
6
2Q
5
Q2Q
12
T
11
2RD
RD
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 3 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
Fig 2. Logic symbol Fig 3. IEC Logic symbol
1Q
Q
S
2REXT/CEXT
13
7
1REXT/CEXT 15
2CEXT 6
1CEXT 14
2Q 5
1Q
Q4
2Q 12
9
001aah797
2A
11A
10 2B
21B
T
31RD
11 2RD
RD
001aah798
CX
&
6
5
12
RCX
R
7
9
11
10
CX
&
14
13
4
RCX
R
15
1
3
2
Fig 4. Logic diagram
001aah799
REXT/CEXT
V
CC
V
CC
V
CC
RD
A
B
CL
CL CL
CL CL
Q
Q
R
R
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Product data sheet Rev. 6 — 19 December 2011 4 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
5. Pinning information
5.1 Pinning
5.2 Pin description
(1) The die substrate is attached to this pad using a
conductive die attach material. It cannot be used as
supply pin or input
Fig 5. Pin configuration DIP1 6, SO16 an d (T)SSOP16 Fig 6. Pin configuration DHVQFN16
74HC423
74HCT423
1A VCC
1B 1REXT/CEXT
1RD 1CEXT
1Q 1Q
2Q 2Q
2CEXT 2RD
2REXT/CEXT 2B
GND 2A
001aah785
1
2
3
4
5
6
7
8
10
9
12
11
14
13
16
15
001aah784
74HC423
74HCT423
2REXT/CEXT 2B
2CEXT 2RD
2Q 2Q
1Q 1Q
1RD 1CEXT
1B 1REXT/CEXT
GND
2A
1A
VCC
Transparent top view
7 10
6 11
5 12
413
3 14
2 15
8
9
1
16
terminal 1
index area
VCC(1)
Table 2. Pin description
Symbol Pin Description
1A, 2A 1, 9 trigger input (negative edge triggered)
1B, 2B 2, 10 trigger input (p ositive edge triggered)
1RD, 2RD 3, 11 direct reset (active LOW)
1Q, 2Q 4, 12 output (active LOW)
GND 8 ground (0 V)
1Q, 2Q 13, 5 output (active HIGH)
1CEXT, 2CEXT 14, 6 external capacitor connection
1REXT/CEXT, 2REXT/CEXT 15, 7 external resistor/capacitor connection
VCC 16 supply voltage
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 5 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
6. Functional description
[1] H = HIGH voltage level;
L = LOW voltage level;
X = don’t care;
= LOW-to-HIGH transition;
= HIGH-to-LOW transition;
= one HIGH level output pulse;
= one LOW level output pulse.
[2] If the monostable multivibrator was triggered before this condition was established, the pulse will continue as programmed.
7. Limiting values
[1] The input and output voltage ratings may be exceeded if the input and output current ratings are observed.
[2] For DIP16 packages: above 70 C the value of Ptot derates linearly at 12 mW/K.
[3] For SO16 packages: above 70 C the value of Ptot derates linearly at 8 mW/K;
For SSOP16 and TSSOP16 packages: above 60 C the value of Ptot derates linearly at 5.5 mW/K;
For DHVQFN16 packages: above 60 C the value of Ptot derates linearly at 4.5 mW/K.
Table 3. Function table[1]
Input Output
nRDnA nB nQ nQ
LXXLH
XHXL
[2] H[2]
XXLL
[2] H[2]
HL
HH
Table 4. Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134). Voltages are referenced to GND (ground = 0 V).
Symbol Parameter Conditions Min Max Unit
VCC supply voltage 0.5 +7 V
IIK input clamping current VI < 0.5 V or VI>V
CC +0.5 V [1] -20 mA
IOK output clamping current VO<0.5 V or VO>V
CC +0.5V [1] -20 mA
IOoutput curren t 0.5 V < VO < VCC +0.5V - 25 mA
ICC supply current - 50 mA
IGND ground current 50 - mA
Tstg storage temperature 65 +150 C
Ptot total power dissipation DIP16 package [2] - 750 mW
SO16, SSOP16, TSSOP16 and
DHVQFN16 packages [3] - 500 mW
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 6 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
8. Recommended operating conditions
9. Static characteristics
Table 5. Recommended operating con ditions
Voltages are referenced to GND (ground = 0 V).
Symbol Parameter Conditions 74HC423 74HCT423 Unit
Min Typ Max Min Typ Max
VCC supply voltage 2.0 5.0 6.0 4.5 5.0 5.5 V
VIinput voltage 0 - VCC 0-V
CC V
VOoutput voltage 0 - VCC 0-V
CC 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
Table 6. Static characteristics
At recommended operating conditions; voltages are referenced to GND (ground = 0 V).
Symbol Parameter Conditions 25 C40 C to
+85 C40 C to
+125 CUnit
Min Typ Max Min Max Min Max
74HC423
VIH 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
VIL 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
VOH HIGH-level
output voltage VI=V
IH or VIL
IO=20 A; VCC = 2.0 V 1.9 2.0 - 1.9 - 1.9 - V
IO=20 A; VCC = 4.5 V 4.4 4.5 - 4.4 - 4.4 - V
IO=20 A; 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
VOL LOW-level
output voltage VI=V
IH or VIL
IO=20A; VCC = 2.0 V - 0 0.1 - 0.1 - 0.1 V
IO=20A; VCC = 4.5 V - 0 0.1 - 0.1 - 0.1 V
IO=20A; VCC = 6.0 V - 0 0.1 - 0.1 - 0.1 V
IO=4.0mA; V
CC = 4.5 V - 0.15 0.26 - 0.33 - 0.4 V
IO=5.2mA; V
CC = 6.0 V - 0.16 0.26 - 0.33 - 0.4 V
IIinput leakage
current VI=V
CC or GND; VCC =6.0V - - 0.1 - 1.0 - 1.0 A
ICC supply current VI=V
CC or GND; IO=0A;
VCC =6.0V - - 8.0 - 80 - 160 A
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Product data sheet Rev. 6 — 19 December 2011 7 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
CIinput capacitance - 3.5 - - - - - pF
74HCT423
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=V
IH or VIL; VCC =4.5V
IO=20 A 4.4 4.5 - 4.4 - 4.4 - V
IO=4.0 mA 3.98 4.32 - 3.84 - 3.7 - V
VOL LOW-level output
voltage VI=V
IH or VIL; VCC =4.5V
IO=20A - 00.1-0.1-0.1V
IO= 4.0 mA - 0.15 0.26 - 0.33 - 0.4 V
IIinput leakage
current VI=V
CC or GND; VCC =5.5V - - 0.1 - 1.0 - 1.0 A
ICC supply current VI=V
CC or GND; VCC =5.5V;
IO=0A - - 8.0 - 80 - 160 A
ICC additional supply
current per input pin; VI=V
CC 2.1 V;
other inputs at VCC or GND;
VCC = 4.5 V to 5.5 V; IO=0A
nA, nB inputs - 35 126 - 158 - 172 A
nRD input - 50 180 - 225 - 245 A
CIinput capacitance - 3.5 - - - - - pF
Table 6. Static characteristics …continued
At recommended operating conditions; voltages are referenced to GND (ground = 0 V).
Symbol Parameter Conditions 25 C40 C to
+85 C40 C to
+125 CUnit
Min Typ Max Min Max Min Max
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 8 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
10. Dynamic characteristics
Table 7. Dynamic characteristics
GND = 0 V; test circuit see Figure 12.
Symbol Parameter Conditions 25 C40 C to
+85 C40 C to
+125 CUnit
Min Typ Max Min Max Min Max
74HC423
tpd propagation
delay nA or nB to nQ or nQ; REXT =5k;
CEXT = 0 pF; see Figure 7 [1]
VCC = 2.0 V - 80 255 - 320 - 385 ns
VCC = 4.5 V - 29 51 - 64 - 77 ns
VCC = 5.0 V; CL=15pF - 25 - - - - - ns
VCC = 6.0 V - 23 43 - 54 - 65 ns
nRD to nQ or nQ; see Figure 7 [1]
VCC = 2.0 V - 66 215 - 270 - 325 ns
VCC = 4.5 V - 24 43 - 54 - 65 ns
VCC = 5.0 V; CL=15pF - 20 - - - - - ns
VCC = 6.0 V - 19 37 - 46 - 55 ns
tttransition time see Figure 7 [2]
VCC = 2.0 V - 19 75 - 95 - 110 ns
VCC = 4.5 V - 7 15 - 19 - 22 ns
VCC = 6.0 V - 6 13 - 16 - 19 ns
tWpulse width nA input LOW; see Figure 7 and Figure 8
VCC = 2.0 V 100 11 - 125 - 150 - ns
VCC = 4.5 V 20 4 - 25 - 30 - ns
VCC = 6.0 V 17 3 - 21 - 26 - ns
nB input HIGH; see Figure 7 and Figure 8
VCC = 2.0 V 100 17 - 125 - 150 - ns
VCC = 4.5 V 20 6 - 25 - 30 - ns
VCC = 6.0 V 17 5 - 21 - 26 - ns
nRD input LOW; see Figure 7 and Figure 8
VCC = 2.0 V 100 14 - 125 - 150 - ns
VCC = 4.5 V 20 5 - 25 - 30 - ns
VCC = 6.0 V 17 4 - 21 - 26 - ns
nQ HIGH or nQ LOW; VCC =5.0 V;
REXT =10k; CEXT = 100 nF;
see Figure 7 and Figure 8
- 450 - - - - - s
nQ HIGH or nQ LOW; VCC =5.0 V;
REXT =5k; CEXT =0pF;
VI=GNDtoV
CC;
see Figure 7 and Figure 8
[3] -75-----ns
trtrig retrigger time nA or nB input; VCC =5.0V; R
EXT =5k;
CEXT = 0 pF; see Figure 10 [4] -110- - - - -ns
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 9 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
REXT external timing
resistor VCC =2.0V; see Figure 8 10 - 1000 - - - - k
VCC =5.0V 2 - 1000 - - - - k
CEXT external timing
capacitor VCC =5.0V; see Figure 8 [5] no limits pF
CPD power
dissipation
capacitance
per package; VI=GNDtoV
CC [6] -54-----pF
74HCT423
tpd propagation
delay nA or nB to nQ or nQ; REXT =5k;
CEXT = 0 pF; see Figure 7
VCC =4.5V [1] -3051-64-77ns
VCC =5.0V; C
L=15pF [1] -26-----ns
nRD to nQ or nQ; REXT =5k;
CEXT = 0 pF; see Figure 7 [1] -2648-60-72ns
VCC =4.5V [1] -2648-60-72ns
VCC =5.0V; C
L=15pF [1] -22-----ns
tttransition ti me VCC = 4.5 V; Figure 7 [2] - 7 15 - 19 - 22 ns
tWpulse width trigger pulse; nA input LOW; VCC = 4.5 V;
see Figure 7 and Figure 10 20 5 - 25 - 30 - ns
trigger pulse; nB input HIGH; VCC = 4.5 V;
see Figure 7 and Figure 10 20 5 - 25 - 30 - ns
reset pulse; nRD input LOW; VCC = 4.5 V;
see Figure 7 and Figure 11 20 7 - 25 - 30 - ns
output pulse; nQ HIGH or nQ LOW;
VCC =5.0 V; R
EXT =10k; CEXT =100nF;
see Figure 7, Figure 10 and Figure 11
- 450 - - - - - s
output pulse; nQ HIGH or nQ LOW;
VCC = 5.0 V; REXT =5k; CEXT =0pF;
VI= GND to VCC 1.5 V; see Figure 7,
Figure 10 and Figure 11
[3] -75-----ns
trtrig retrigger time nA or nB input; VCC =5.0V; R
EXT =5k;
CEXT = 0 pF; see Figure 10 -110- - - - -ns
REXT external timing
resistor VCC =5.0V; see Figure 8 2 - 1000 - - - - k
CEXT external timing
capacitor VCC =5.0V; see Figure 8 [5] no limits pF
Table 7. Dynamic characteristics …continued
GND = 0 V; test circuit see Figure 12.
Symbol Parameter Conditions 25 C40 C to
+85 C40 C to
+125 CUnit
Min Typ Max Min Max Min Max
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 10 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
[1] tpd is the same as tPHL and tPLH.
[2] tt is the same as tTHL and tTLH.
[3] For other REXT and CEXT combinations see Figure 8. If CEXT > 10 pF, the next formula is valid:
tW = K REXT CEXT (typ.), where:
tW = output pulse width in ns;
REXT = external resistor in k;
CEXT = external capacitor in pF;
K = 0.55 for VCC = 2.0 V and 0.45 for VCC = 5.0 V; see Figure 9.
Inherent test jig and pin capacitance at pins 15 and 7 (nREXT/CEXT) is 7 pF.
[4] The time to retrigger the monostable multivibrator depends on the values of REXT and CEXT. The output pulse width will only be
extended when the time between the active-going edges of the trigger input pulses meets the minimum retrigger time.
If CEXT > 10 pF, the next formula (at VCC = 5.0 V) for the set-up time of a retrigger pulse is valid:
trtrig = 30 + 0.19 REXT CEXT0.9 + 13 REXT1.05 (typ.); where:
trtrig = retrigger time in ns;
CEXT = external capacitor in pF;
REXT = external resistor in k.
Inherent test jig and pin capacitance at pins 15 and 7 (nREXT/CEXT) is 7 pF.
[5] When the device is powered-up, initiate the device via a reset pulse, when CEXT < 50 pF.
[6] CPD is used to determine the dynamic power dissipation (PD in W):
PD=C
PD VCC2fiN+(CLVCC2fo); where:
fi= input frequency in MHz;
fo= output frequency in MHz;
CL= output load capacitance in pF;
VCC = supply voltage in V;
N = number of inputs switching;
(CLVCC2fo) = sum of outputs.
CPD power
dissipation
capacitance
per package; VI=GNDtoV
CC 1.5 V [6] -56-----pF
Table 7. Dynamic characteristics …continued
GND = 0 V; test circuit see Figure 12.
Symbol Parameter Conditions 25 C40 C to
+85 C40 C to
+125 CUnit
Min Typ Max Min Max Min Max
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 11 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
11. Waveforms
Measurement points are given in Table 8.
VOL and VOH are typical voltage output levels that occur with the output load.
Fig 7. Pu lse widths, propagation delays from inputs (nA, nB, nRD) to outputs (nQ, nQ) and
output transition times
001aah911
nB input
VI
GND
VOH
VOL
VOH
VOL
VI
GND
VI
GND
tW
tW
tPLH
VM
VM
VY
VY
VX
VX
VM
tW
tTLH
tTHL
tPLH
tTHL
tPHL
tPHL (reset)
VM
tW
nA input
nRD input
nQ output
nQ output
VM
tW
tPLH (reset)tPHL
tPHL
tTLH
tPLH
Table 8. Measurement points
Type Input Output
VIVMVMVXVY
74HC423 VCC 0.5VCC 0.5VCC 0.1VCC 0.9VCC
74HCT423 3 V 1.3 V 1.3 V 0.1VCC 0.9VCC
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Product data sheet Rev. 6 — 19 December 2011 12 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
VCC = 5.0 V and Tamb = 25 C.
(1) REXT = 100 k.
(2) REXT = 50 k.
(3) REXT = 10 k.
(4) REXT = 2 k.
External capacitance = 10 nF,
external resistance = 10 k to 100 k and Tamb =25C.
Fig 8. Typical output pulse width as a function of the
external capacitor values Fig 9. Typical ‘K’ factor
001aaa611
103
102
105
104
106
tW
(ns)
10
CEXT (pF)
110
4
103
10 102
(2)
(3)
(4)
(1)
VCC (V)
08624
001aaa612
0.4
0.2
0.6
0.8
'K' factor
0
nRD = HIGH.
Fig 10. Output pulse control using retrigger pulse (t rtrig)
mna521
tWtW
tW
tW
tW
nB input
nA input
nQ output
trtrig
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Product data sheet Rev. 6 — 19 December 2011 13 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
nA = LOW.
Fig 11. Output pulse control using reset input nR D
mna522
tWtW
tW
nB input
nRD input
nQ output
Test data is given in Table 9.
Definitions for test circuit:
RT = Termination resistance should be equal to output impedance Zo of the pulse generator.
CL = Load capacitance including jig and probe capacitance.
Fig 12. Test circuit for measuring switching times
001aah768
tW
tW
tr
tr
tf
VM
VI
negative
pulse
GND
VI
positive
pulse
GND
10 %
90 %
90 %
10 % VMVM
VM
tf
VCC
DUT
RT
VIVO
CL
G
Table 9. Test data
Supply Input Load
VCC VItr, tfCL
2.0 V to 6.0 V VCC 6 ns 15 pF, 50 pF
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Product data sheet Rev. 6 — 19 December 2011 14 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
12. Application information
12.1 T iming component connections
The basic output pulse wid th is essentially determined by the values of the external timing
components REXT and CEXT.
12.1.1 Minimum monostable pulse width
To set the minimum pulse width, when CEXT < 10 nF, see Figure 8 and
when CEXT > 10 nF, the output pulse width is defined as:
tW = 0.45 REXT CEXT (typ.), where:
tW = pulse width in s;
REXT = external resistor in k;
CEXT = external capacitor in nF.
12.2 Power-up considerations
When the monostable is powered-up it may produce an output pulse, with a pulse width
defined by the values of REXT and CEXT, this output pulse can be eliminated using the
circuit shown in Figure 14.
(1) For minimum noise generation it is recommended that the nCEXT pins (6, 14) are connected to ground externally to
the GND pin (8).
Fig 13. Timing component connections
001aah917
CEXT REXT
nA
nB
V
CC
nCEXT
nRD
nREXT/CEXT
nQ
nQ
GND
423 13 (5)
4 (12)
15 (7)14 (6)
3 (11)
8
1 (9)
2 (10)
(1)
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Product data sheet Rev. 6 — 19 December 2011 15 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
12.3 Power-down considerations
A large capacitor CEXT may cause problems when powering-d own the mono stable due to
the capacitor’s stored energy . When a system containing this device is po wered-down or a
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 15.
Fig 14. Power-up output pulse elimination circuit
001aah918
V
CC
RESET nRD
CEXT REXT
nA
nB
V
CC
nCEXTGND nREXT/CEXT
nQ
nQ
423 13 (5)
4 (12)
15 (7)14 (6)8
1 (9)
2 (10)
3 (11)
Fig 15. Power-down protec tion circuit
001aah919
DEXT
nRD
CEXT REXT
nA
nB
VCC
nCEXT nREXT/CEXT
nQ
nQ
423 13 (5)
4 (12)
15 (7)
1 (9)
2 (10)
3 (11)
GND
14 (6)8
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 16 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
13. Package outline
Fig 16. Package outline SOT38-4 (DIP16)
REFERENCES
OUTLINE
VERSION EUROPEAN
PROJECTION ISSUE DATE
IEC JEDEC JEITA
SOT38-4 95-01-14
03-02-13
MH
c
(e )
1
ME
A
L
seating plane
A1
wM
b1
b2
e
D
A2
Z
16
1
9
8
E
pin 1 index
b
0 5 10 mm
scale
Note
1. Plastic or metal protrusions of 0.25 mm (0.01 inch) maximum per side are not included.
UNIT A
max. 12 b1(1) (1) (1)
b2cD E e M Z
H
L
mm
DIMENSIONS (inch dimensions are derived from the original mm dimensions)
A
min. A
max. bmax.
w
ME
e1
1.73
1.30 0.53
0.38 0.36
0.23 19.50
18.55 6.48
6.20 3.60
3.05 0.2542.54 7.62 8.25
7.80 10.0
8.3 0.764.2 0.51 3.2
inches 0.068
0.051 0.021
0.015 0.014
0.009
1.25
0.85
0.049
0.033 0.77
0.73 0.26
0.24 0.14
0.12 0.010.1 0.3 0.32
0.31 0.39
0.33 0.030.17 0.02 0.13
DIP16: plastic dual in-line package; 16 leads (300 mil) SOT38-4
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 17 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
Fig 17. Package outline SOT109-1 (SO16)
X
wM
θ
A
A1
A2
bp
D
HE
Lp
Q
detail X
E
Z
e
c
L
vMA
(A )
3
A
8
9
1
16
y
pin 1 index
UNIT A
max. A1A2A3bpcD
(1) E(1) (1)
eH
ELL
pQZywv θ
REFERENCES
OUTLINE
VERSION EUROPEAN
PROJECTION ISSUE DATE
IEC JEDEC JEITA
mm
inches
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 0.7
0.6 0.7
0.3 8
0
o
o
0.25 0.1
DIMENSIONS (inch dimensions are derived from the original mm dimensions)
Note
1. Plastic or metal protrusions of 0.15 mm (0.006 inch) maximum per side are not included.
1.0
0.4
SOT109-1 99-12-27
03-02-19
076E07 MS-012
0.069 0.010
0.004 0.057
0.049 0.01 0.019
0.014 0.0100
0.0075 0.39
0.38 0.16
0.15 0.05
1.05
0.041
0.244
0.228 0.028
0.020 0.028
0.012
0.01
0.25
0.01 0.004
0.039
0.016
0 2.5 5 mm
scale
SO16: plastic small outline package; 16 leads; body width 3.9 mm SOT109-1
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 18 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
Fig 18. Package outline SOT763-1 (DHVQFN16)
terminal 1
index area
0.51
A1Eh
b
UNIT ye
0.2
c
REFERENCES
OUTLINE
VERSION EUROPEAN
PROJECTION ISSUE DATE
IEC JEDEC JEITA
mm 3.6
3.4
Dh
2.15
1.85
y1
2.6
2.4 1.15
0.85
e1
2.5
0.30
0.18
0.05
0.00 0.05 0.1
DIMENSIONS (mm are the original dimensions)
SOT763-1 MO-241 - - -- - -
0.5
0.3
L
0.1
v
0.05
w
0 2.5 5 mm
scale
SOT763-1
DHVQFN16: plastic dual in-line compatible thermal enhanced very thin quad flat package; no leads;
16 terminals; body 2.5 x 3.5 x 0.85 mm
A(1)
max.
AA1c
detail X
y
y1C
e
L
Eh
Dh
e
e1
b
27
15 10
9
8
1
16
X
D
E
C
BA
terminal 1
index area
AC
CB
vM
wM
E(1)
Note
1. Plastic or metal protrusions of 0.075 mm maximum per side are not included.
D(1)
02-10-17
03-01-27
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 19 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
Fig 19. Package outline SOT338-1 (SSOP16)
UNIT A1A2A3bpcD
(1) E(1) eH
ELL
pQZywv θ
REFERENCES
OUTLINE
VERSION EUROPEAN
PROJECTION ISSUE DATE
IEC JEDEC JEITA
mm 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 1.25
7.9
7.6 1.03
0.63 0.9
0.7 1.00
0.55 8
0
o
o
0.130.2 0.1
DIMENSIONS (mm are the original dimensions)
Note
1. Plastic or metal protrusions of 0.25 mm maximum per side are not included.
SOT338-1 99-12-27
03-02-19
(1)
wM
bp
D
HE
E
Z
e
c
vMA
X
A
y
18
16 9
θ
A
A1
A2
Lp
Q
detail X
L
(A )
3
MO-150
pin 1 index
0 2.5 5 mm
scale
SSOP16: plastic shrink small outline package; 16 leads; body width 5.3 mm SOT338-1
A
max.
2
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 20 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
Fig 20. Package outline SOT403-1 (TSSOP16)
UNIT A1A2A3bpcD
(1) E(2) (1)
eH
ELL
pQZywv θ
REFERENCES
OUTLINE
VERSION EUROPEAN
PROJECTION ISSUE DATE
IEC JEDEC JEITA
mm 0.15
0.05 0.95
0.80 0.30
0.19 0.2
0.1 5.1
4.9 4.5
4.3 0.65 6.6
6.2 0.4
0.3 0.40
0.06 8
0
o
o
0.13 0.10.21
DIMENSIONS (mm are the original dimensions)
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.
0.75
0.50
SOT403-1 MO-153 99-12-27
03-02-18
wM
bp
D
Z
e
0.25
18
16 9
θ
A
A1
A2
Lp
Q
detail X
L
(A )
3
HE
E
c
vMA
X
A
y
0 2.5 5 mm
scale
TSSOP16: plastic thin shrink small outline package; 16 leads; body width 4.4 mm SOT403-1
A
max.
1.1
pin 1 index
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 21 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
14. Abbreviations
15. Revision history
Table 10. Abbreviations
Acronym Description
CMOS Complementary Metal Oxide Semiconductor
DUT Device Under Test
ESD ElectroStatic Discharge
HBM Human Body Model
MM Machine Model
TTL Transistor-Transistor Logic
Table 11. Revision history
Document ID Release date Data sheet status Change notice Supersedes
74HC_HCT423 v.6 20111219 Product data sheet - 74HC_HCT423 v.5
Modifications: •Legal pages updated.
74HC_HCT423 v.5 20110825 Product data sheet - 74HC_HCT423 v.4
74HC_HCT423 v.4 20110318 Product data sheet - 74HC_HCT423 v.3
74HC_HCT423 v.3 20080724 Product data sheet - 74HC_HCT423_CNV v.2
74HC_HCT423_CNV v.2 19980708 Product specification - -
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 22 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
16. Legal information
16.1 Data sheet status
[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 de vice(s) descr ibed in th is docume nt may have cha nged since this docume nt was publis hed and ma y dif fer 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 liab ility 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 tit le. A short data sh eet is intended
for quick reference only and shou ld not be rel ied u pon to cont ain det ailed 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 conf lict with the short data sheet, the
full data sheet shall pre vail.
Product specificat ion — The information and data provided in a Product
data sheet shall define the specification of the product as agreed between
NXP Semiconductors and its customer, unless NXP Semiconductors and
customer have explicitly agreed otherwise in writing. In no event however,
shall an agreement be valid in which the NXP Semiconductors product is
deemed to off er functions and qualities beyond those described in the
Product data sheet.
16.3 Disclaimers
Limited warr a nty and liability — 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.
In no event shall NXP Semiconductors be liable for any indirect, incidental ,
punitive, special or consequ ential damages (including - wit hout limitatio n - lost
profits, lost savings, business interruption, costs related to the removal or
replacement of any products or rework charges) whether or not such
damages are based on tort (including negligence), warranty, breach of
contract or any other legal theory.
Notwithstanding any damages that customer might incur for any reason
whatsoever, NXP Semiconductors’ aggreg ate and cumulative l iability towards
customer for the products described herein shall be limited in accordance
with the Terms and conditions of commercial sale of NXP Semiconductors.
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 informa tion supplied prior
to the publication hereof .
Suitability for use — NXP Semiconductors products are not designed,
authorized or warranted to be suit able for use in life support, life-crit ical or
safety-critical systems or equipment, nor in applications where failure or
malfunction of an NXP Semiconductors pro duct can reasonably be expected
to result in perso nal injury, death or severe property or environmental
damage. NXP Semiconductors accepts no liab ility 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 tha t such application s will be suitable for the
specified use without further testing or modification.
Customers are responsible for the design and ope ration of their applications
and products using NXP Semiconductors product s, and NXP Semiconductors
accepts no liability for any assistance with applications or customer product
design. It is customer’s sole responsibility to determine whether the NXP
Semiconductors product is suit able and fit for the custome r’s applications and
products planned, as well as fo r the planned application and use of
customer’s third party customer(s). Customers should provide appropriate
design and operating safeguards to minimize the risks associated with their
applications and products.
NXP Semiconductors does not accept any liabili ty related to any default,
damage, costs or problem which is based on any weakness or default in the
customer’s applications or products, or the application or use by customer’s
third party customer(s). Customer is responsible for doing all necessa ry
testing for th e customer’s applications and pro ducts using NXP
Semiconductors products in order to avoid a default of the applications and
the products or of the application or use by cust omer’s third party
customer(s). NXP does not accept any liability in this respect.
Limiting values — Stress above one or more limiting values (as defined in
the Absolute Maximum Ratings System of IEC 60134) will cause permanent
damage to the device. Limiting values are stress ratings only and (proper)
operation of the device at these or any other conditions above those given in
the Recommended operating conditions section (if present) or the
Characteristics sections of this document is not warranted. Constant or
repeated exposure to limiting values will permanent ly and irreversibly affect
the quality and reliability of the device.
Terms and conditions of commercial 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, unless otherwise
agreed in a valid written individua l agreement. In case an individual
agreement is concluded only the ter ms and conditions of the respective
agreement shall apply. NXP Semiconductors hereby expressly objects to
applying the customer’s general terms and conditions with regard to the
purchase of NXP Semiconductors products by customer.
No offer to sell or license — Nothing i n this document may be interpreted or
construed as an of fer t o sell product s that is open for accept ance or t he 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 regulatio ns. Export might require a prior
authorization from competent authorities.
Document status[1][2] Product status[3] Definition
Objective [short] data sheet Development This document contains data from the obj ective specification for product development.
Preliminary [short] dat a sheet Qualification This document contains data from the preliminary specification.
Product [short] dat a sheet Production This document contains the product specification.
74HC_HCT423 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 6 — 19 December 2011 23 of 24
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
Non-automotive qualified products — Unless this data sheet expressly
states that this specific NXP Semiconductors product is automotive qualified,
the product is not suitable for aut omo tive use. It i s neit her qua lif ied nor tested
in accordance with automotive testing or application requirements. NXP
Semiconductors accepts no liability for inclusion and/or use of
non-automotive qualified products in automotive equipment or applications.
In the event that customer uses the product for design-in and use in
automotive applications to automot ive specifications and standard s, customer
(a) shall use the product without NXP Semiconductors’ warranty of the
product for such automotive applications, use and specifications, and (b)
whenever customer uses the product for automotive applications beyond
NXP Semiconductors’ specifications such use shall be solely at customer’s
own risk, and (c) customer fully indemnifies NXP Semiconductors for any
liability, damages or failed product claims resulting f rom customer design an d
use of the product for automotive applications beyond NXP Semiconductors’
standard warranty and NXP Semiconductors’ product specif ications.
16.4 Trademarks
Notice: All referenced b rands, produc t names, service names and trademarks
are the property of their respect i ve ow ners.
17. Contact information
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: salesaddresses@nxp.com
NXP Semiconductors 74HC423; 74HCT423
Dual retriggerable monostable multivibrator with reset
© NXP B.V. 2011. All rights reserved.
For more information, please visit: http://www.nxp.co m
For sales office addresses, please send an email to: salesaddresses@nxp.com
Date of release: 19 December 2011
Document identifier: 74HC_HCT423
Please be aware that important notices concerning this document and the product(s)
described herein, have been included in section ‘Legal information’.
18. Contents
1 General description. . . . . . . . . . . . . . . . . . . . . . 1
2 Features and benefits . . . . . . . . . . . . . . . . . . . . 1
3 Ordering information. . . . . . . . . . . . . . . . . . . . . 2
4 Functional diagram . . . . . . . . . . . . . . . . . . . . . . 2
5 Pinning information. . . . . . . . . . . . . . . . . . . . . . 4
5.1 Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
5.2 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 4
6 Functional description . . . . . . . . . . . . . . . . . . . 5
7 Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . . 5
8 Recommended operating conditions. . . . . . . . 6
9 Static characteristics. . . . . . . . . . . . . . . . . . . . . 6
10 Dynamic characteristics . . . . . . . . . . . . . . . . . . 8
11 Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
12 Application information. . . . . . . . . . . . . . . . . . 14
12.1 Timing component connections . . . . . . . . . . . 14
12.1.1 Minimum monostable pulse width. . . . . . . . . . 14
12.2 Power-up considerations . . . . . . . . . . . . . . . . 14
12.3 Power-down considerations . . . . . . . . . . . . . . 15
13 Package outline . . . . . . . . . . . . . . . . . . . . . . . . 16
14 Abbreviations. . . . . . . . . . . . . . . . . . . . . . . . . . 21
15 Revision history. . . . . . . . . . . . . . . . . . . . . . . . 21
16 Legal information. . . . . . . . . . . . . . . . . . . . . . . 22
16.1 Data sheet status . . . . . . . . . . . . . . . . . . . . . . 22
16.2 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
16.3 Disclaimers. . . . . . . . . . . . . . . . . . . . . . . . . . . 22
16.4 Trademarks. . . . . . . . . . . . . . . . . . . . . . . . . . . 23
17 Contact information. . . . . . . . . . . . . . . . . . . . . 23
18 Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
