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74LV123
Dual retriggerable monostable
multivibrator with reset
Product specification
Supersedes data of 1997 Feb 04
IC24 Data Handbook
1998 Apr 20
INTEGRATED CIRCUITS
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
2
1998 Apr 28 853–1911 19290
FEATURES
•Optimized for Low V oltage applications: 1.0 to 5.5V
•Accepts TTL input levels between VCC = 2.7V and VCC = 3.6V
•Typical VOLP (output ground bounce) 0.8V @ VCC = 3.3V,
Tamb = 25°C
•Typical VOHV (output VOH undershoot) 2V @ VCC = 3.3V,
Tamb = 25°C
•DC triggered from active HIGH or active LOW inputs
•Retriggerable for very long pulses up to 100% duty factor
•Direct reset terminates output pulses
•Schmitt-trigger action on all inputs except for the reset input
•Output capability: standard (except for nREXT/CEXT)
•ICC category: MSI
DESCRIPTION
The 74LV123 is a low-voltage Si-gate CMOS device and is pin and
function compatible with the 74HC/HCT123.
The 74LV123 is a dual retriggerable monostable multivibrator with
output pulse width control by three methods. The basic pulse time is
programmed by selection of an external resistor (REXT) and
capacitor (CEXT). They are normally connected as shown in
Figure 1. 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 input (nB). By repeating this
process, the output pulse period (nQ = HIGH, nQ = LOW) can be
made as long as desired. Alternatively, an output delay can be
terminated at any time by a LOW-going edge on input nRD, which
also inhibits the triggering. Figures 1 and 2 illustrate pulse control by
retriggering and early reset. The basic output pulse width is
essentially determined by the values of the external timing
components REXT and CEXT. For pulse width when CEXT <10000pF,
see Figure 5. When CEXT 10,000pF, the typical output pulse
width is defined as: tW = 0.45 REXT CEXT (typ.), where
tW= pulse width in ns; REXT = external resistor in KΩ; and
CEXT = external capacitor in pF. Schmitt-trigger action in the nA and
nB inputs makes the circuit highly tolerant of slower input rise and
fall times.
QUICK REFERENCE DATA
GND = 0V ; Tamb = 25°C; tr = tf 2.5 ns
SYMBOL PARAMETER CONDITIONS TYPICAL UNIT
tPHL/tPLH Propagation delay
nA, nB to nQ, nQ
nRD to nQ, nQ
CL = 15pF
VCC = 3.3V
REXT = 5KΩ
CEXT = 0pF 25
20 ns
ns
CIInput capacitance 3.5 pF
CPD Power dissipation capacitance per monost-
able VCC = 3.3V, VI = GND to VCC160 pF
NOTES:
1. CPD is used to determine the dynamic power dissipation (PD in µW)
PD = CPD VCC2 fi (CL VCC2 fo) where:
fi = input frequency in MHz; CL = output load capacitance in pF;
fo = output frequency in MHz; VCC = supply voltage in V ;
(CL VCC2 fo) = sum of the outputs.
ORDERING INFORMATION
PACKAGES TEMPERATURE RANGE OUTSIDE NORTH AMERICA NORTH AMERICA PKG. DWG. #
16-Pin Plastic DIL –40°C to +125°C74LV123 N 74LV123 N SOT38-1
16-Pin Plastic SO –40°C to +125°C74LV123 D 74LV123 D SOT109-1
16-Pin Plastic SSOP Type II –40°C to +125°C74LV123 DB 74LV123 DB SOT338-1
16-Pin Plastic TSSOP Type I –40°C to +125°C74LV123 PW 74LV123PW DH SOT403-1
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
1998 Apr 28 3
PIN CONFIGURATION
14
13
12
11
10
9
7
6
5
4
3
2
1
GND
VCC
1A
1B
1RD
1Q
2Q
8
15
16
2CEXT
2REXT/CEXT
1REXT/CEXT
1CEXT
1Q
2Q
2RD
2B
2A
SV00096
PIN DESCRIPTION
PIN
NUMBER SYMBOL FUNCTION
1,9 1A, 2A T rigger inputs
(negative-edge triggered)
2,10 1B, 2B T rigger inputs
(positive-edge triggered)
3,11 1RD, 2RDDirect reset LOW and trigger action at
positive edge
4, 12 1Q, 2Q Outputs (active LOW)
7 2REXT/CEXT External resistor/capacitor connection
8 GND Ground (0V)
13, 5 1Q, 2Q Outputs (active HIGH)
14, 6 1CEXT,
2CEXT External capacitor connection
15 1REXT/CEXT External resistor/capacitor connection
16 VCC Positive supply voltage
LOGIC SYMBOL (IEEE/IEC)
CX
RCX
&
R
14
15
1
2
3
13
4
CX
RCX
&
R
6
7
9
10
11
5
12
SV00098
LOGIC SYMBOL
1
9
2
10
3
11
14
6
15
7
13
5
4
12
1A
2A
1B
2B
1RD
2RD
1CEXT
2CEXT
1REXT/CEXT
2REXT/CEXT
1Q
2Q
1Q
2Q
S
Q
Q
RD
T
SV00097
FUNCTIONAL DIAGRAM
1
9
2
10
3
11
14
6
15
7
13
5
4
12
1A
2A
1B
2B
1RD
2RD
1CEXT
2CEXT
1REXT/CEXT
2REXT/CEXT
1Q
2Q
1Q
2Q
S
Q
Q
RD
T
SV00099
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
1998 Apr 28 4
LOGIC DIAGRAM
R
nREXT/CEXT
VCC
Q
Q
RD
RR
CL
CL
VCC CL
CLCL
R
A
B
SV00100
VCC
It is recommended that Pin 6 (2CEXT) and Pin 14 (1CEXT) by externally grounded to Pin 8 (GND)
FUNCTION TABLE
INPUTS OUTPUTS
nRDnA nB nQ nQ
L X X L H
X H X L * H *
X X L L * H *
H L ↑
H↓H
↑L H
NOTES:
* If the monostable was triggered before this condition was
established, the pulse will continue as programmed.
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
VCC
REXT
CEXT
to nCEXT
(pin 14 or 6) to nREXT/CEXT
(pin 15 or 7)
SV00101
Figure 1.Timing component connection
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
1998 Apr 28 5
RECOMMENDED OPERATING CONDITIONS
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNIT
VCC DC supply voltage See Note11.0 3.3 5.5 V
VIInput voltage 0 – VCC V
VOOutput voltage 0 – VCC V
Tamb Operating ambient temperature range in free
air See DC and AC
characteristics –40
–40 +85
+125 °C
tr, tfInput rise and fall times except for
Schmitt-trigger inputs
VCC = 1.0V to 2.0V
VCC = 2.0V to 2.7V
VCC = 2.7V to 3.6V
VCC = 3.6V to 5.5V
–
–
–
–
–
–
–
–
500
200
100
50 ns/V
NOTE:
1. The LV is guaranteed to function down to VCC = 1.0V (input levels GND or VCC); DC characteristics are guaranteed from VCC = 1.2V to VCC = 5 .5V.
ABSOLUTE MAXIMUM RATINGS1, 2
In accordance with the Absolute Maximum Rating System (IEC 134).
Voltages are referenced to GND (ground = 0V).
SYMBOL PARAMETER CONDITIONS RATING UNIT
VCC DC supply voltage –0.5 to +7.0 V
IIK DC input diode current VI < –0.5 or VI > VCC + 0.5V 20 mA
IOK DC output diode current VO < –0.5 or VO > VCC + 0.5V 50 mA
IODC output source or sink current
– standard outputs –0.5V < VO < VCC + 0.5V 25 mA
IGND,
ICC
DC VCC or GND current for types with
– standard outputs 50 mA
Tstg Storage temperature range –65 to +150 °C
PTOT
Power dissipation per package
– plastic DIL
– plastic mini-pack (SO)
– plastic shrink mini-pack (SSOP and TSSOP)
for temperature range: –40 to +125°C
above +70°C derate linearly with 12 mW/K
above +70°C derate linearly with 8 mW/K
above +60°C derate linearly with 5.5 mW/K
750
500
500 mW
NOTES:
1. Stresses beyond those listed may cause permanent damage to the device. These are stress ratings only and functional operation of the
device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to
absolute-maximum-rated conditions for extended periods may affect device reliability.
2. The input and output voltage ratings may be exceeded if the input and output current ratings are observed.
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
1998 Apr 28 6
DC ELECTRICAL CHARACTERISTICS
Over recommended operating conditions. Voltages are referenced to GND (ground = 0V). LIMITS
SYMBOL PARAMETER TEST CONDITIONS -40°C to +85°C -40°C to +125°CUNIT
MIN TYP1MAX MIN MAX
VCC = 1.2V 0.9 0.9
V
HIGH level Input VCC = 2.0V 1.4 1.4
V
V
IH voltage VCC = 2.7 to 3.6V 2.0 2.0
V
VCC = 4.5 to 5.5V 0.7VCC 0.7VCC
VCC = 1.2V 0.3 0.3
V
LOW level Input VCC = 2.0V 0.6 0.6
V
V
IL voltage VCC = 2.7 to 3.6V 0.8 0.8
V
VCC = 4.5 to 5.5 0.3VCC 0.3VCC
VCC = 1.2V ; V I = VIH or VIL; –IO = 100µA 1.2
HIGH l l t t
VCC = 2.0V ; V I = VIH or VIL; –IO = 100µA 1.8 2.0 1.8
VOH HIGH level output
voltage
;
all out
p
uts
VCC = 2.7V ; V I = VIH or VIL; –IO = 100µA 2.5 2.7 2.5 V
voltage
all
out uts
VCC = 3.0V ; V I = VIH or VIL; –IO = 100µA 2.8 3.0 2.8
VCC = 4.5V ; V I = VIH or VIL; –IO = 100µA 4.3 4.5 4.3
VO
HIGH level output
volta
g
e; VCC = 3.0V ; V I = VIH or VIL; –IO = 6mA 2.40 2.82 2.20
V
V
OH
g
STANDARD
outputs VCC = 4.5V ; V I = VIH or VIL; –IO = 12mA 3.60 4.20 3.50
V
VCC = 1.2V ; V I = VIH or VIL; IO = 100µA 0
LOW l l t t
VCC = 2.0V ; V I = VIH or VIL; IO = 100µA 0 0.2 0.2
VOL LOW level output
voltage
;
all out
p
uts
VCC = 2.7V ; V I = VIH or VIL; IO = 100µA 0 0.2 0.2 V
voltage
all
out uts
VCC = 3.0V ; V I = VIH or VIL; IO = 100µA 0 0.2 0.2
VCC = 4.5V ; V I = VIH or VIL; IO = 100µA 0 0.2 0.2
VO
LOW level output
volta
g
e; VCC = 3.0V ; V I = VIH or VIL; IO = 6mA 0.25 0.40 0.50
V
V
OL
g
STANDARD
outputs VCC = 4.5V ; V I = VIH or VIL; IO = 12mA 0.35 0.55 0.65
V
IIInput leakage
current VCC = 5.5V ; V I = VCC or GND 1.0 1.0 µA
ICC Quiescent supply
current; MSI VCC = 5.5V ; V I = VCC or GND; IO = 0 20.0 160 µA
∆ICC Additional
quiescent supply
current VCC = 2.7V to 3.6V ; VI = VCC – 0.6V 500 850 µA
NOTES:
1. All typical values are measured at Tamb = 25°C.
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
1998 Apr 28 7
AC CHARACTERISTICS
GND = 0V ; tr = tf ≤ 2.5ns; C L = 50pF; RL =1 KΩ
CONDITION
LIMITS
SYMBOL PARAMETER WAVEFORM
CONDITION
–40 to +85°C–40 to +125°CUNIT
VCC(V) MIN TYP1MAX MIN MAX
1.2 120
Propagation delay
Fi
g
ure 3 2.0 40 76 92
tPHL
P
ropaga
ti
on
d
e
l
ay
nRD,nA, nB, to nQ
Figure
3
CEXT = 0pF
R 5KΩ
2.7 30 56 68 ns
nRD
,
nA
,
nB
,
to
nQ
R
EXT = 5
K
Ω3.0 to 3.6 25248 57
4.5 to 5.5 18240 46
1.2 120
Propagation delay
Fi
g
ure 3 2.0 40 76 92
tPLH
P
ropaga
ti
on
d
e
l
ay
nRD,nA, nB, to nQ
Figure
3
CEXT = 0pF
R 5KΩ
2.7 30 56 68 ns
nRD
,
nA
,
nB
,
to
nQ
R
EXT = 5
K
Ω3.0 to 3.6 25248 57
4.5 to 5.5 182 40 46
1.2 100
Propagation delay
Fi
g
ure 3 2.0 30 57 68
tPHL
P
ropaga
ti
on
d
e
l
ay
nRDto nQ (reset)
Figure
3
CEXT = 0pF
R 5KΩ
2.7 23 43 51 ns
nRD
to
nQ
(reset)
R
EXT = 5
K
Ω3.0 to 3.6 20238 45
4.5 to 5.5 14231 36
1.2 100
Propagation delay
Fi
g
ure 3 2.0 30 57 68
tPLH
P
ropaga
ti
on
d
e
l
ay
nRDto nQ (reset)
Figure
3
CEXT = 0pF
R 5KΩ
2.7 23 43 51 ns
nRD
to
nQ
(reset)
R
EXT = 5
K
Ω3.0 to 3.6 20238 45
4.5 to 5.5 14231 36
2.0 30 5 40
tW
T rigger pulse width
Figure 3
2.7 25 3.5 30
ns
t
W
gg
nA = LOW
Figure
3
3.0 to 3.6 20 3.0225
ns
4.5 to 5.5 15 2.5220
2.0 30 13 40
tW
T rigger pulse width
Figure 3
2.7 25 8 30
ns
t
W
gg
nB = HIGH
Figure
3
3.0 to 3.6 20 7225
ns
4.5 to 5.5 15 5220
2.0 35 6 45
tW
Reset pulse width
Figure 2
2.7 30 5 40
ns
t
WnRD = LOW
Figure
2
3.0 to 3.6 25 4230
ns
4.5 to 5.5 20 3225
2.0 470
tW
Output pulse width
nQ = HIGH
Figures 1, 2
CEXT = 100nF
2.7 460
µs
t
W
nQ
=
HIGH
nQ = LOW
C
EXT =
100nF
R
EXT
= 10KΩ3.0 to 3.6 4502
µs
Q
EXT
4.5 to 5.5 4302
2.0 100
tW
Output pulse width
nQ = HIGH
Figures 1, 2
CEXT =0
p
F
2.7 90
ns
t
W
nQ
=
HIGH
nQ = LOW
C
EXT =
0F
R
EXT
= 5KΩ3.0 to 3.6 802
ns
Q
EXT
4.5 to 5.5 702
2.0 70
tt
Retrigger time Figure 1
CEXT =0
p
F
2.7 55
ns
t
rt
gg
nA, nB
C
EXT =
0F
R
EXT
= 5KΩ3.0 to 3.6 452
ns
EXT
4.5 to 5.5 402
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
1998 Apr 28 8
AC CHARACTERISTICS (Continued)
GND = 0V ; tr = tf ≤ 2.5ns; C L = 50pF; RL =1 KΩ
CONDITION
LIMITS
SYMBOL PARAMETER WAVEFORM
CONDITION
–40 to +85°C–40 to +125°CUNIT
VCC(V) MIN TYP MAX MIN MAX
1.2 10 1000
External timing
2.0 5 1000
REXT
E
x
t
erna
l
ti
m
i
ng
resistor
Figure 5 2.7 3 1000 ΚΩ
resistor
3.0 to 3.6 2 1000
4.5 to 5.5 2 1000
3
1.2
External timing
3
2.0
CEXT
E
x
t
erna
l
ti
m
i
ng
ca
p
acitor
Figure 5
3
2.7 No limits pF
ca acitor
3.0 to 3.6
4.5 to 5.5
NOTES:
1. Unless otherwise stated, all typical values are at Tamb = 25°C.
2. Typical value measured at VCC = 3.3V.
3. Typical value measured at VCC = 5.0V.
4. For other REXT and CEXT combinations see Figure 5.
if CEXT > 10 nF, the next formula is valid:
tW= K x REXT x CEXT (typ.)
where, tW= output pulse width in ns;
REXT = external resistor in KΩ; CEXT = external capacitor in pF;
K = constant = 0.45 for VCC = 5.0V and 0.48 for VCC = 2.0V.
The inherent test jig and pin capacitance at pins 15 and 7 (nREXT/CEXT) is approximately 7 pF.
5. 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 pulses meets the minimum retrigger time.
If CEXT > 10 pF, the next formula (at VCC = 5.0V) for the set-up time of a retrigger pulse is valid:
trt = 30 + 0.19R x C-9 + 13 x R1.05 (typ.)
where, trt = retrigger time in ns;
CEXT = external capacitor in pF;
REXT = external resistor in KΩ.
The inherent test jig and pin capacitance at pins 15 and 7 (nREXT/CEXT) is approximately 7 pF.
6. When the device is powered up, initiate the device via a reset pulse, when CEXT < 50pF.
AC WAVEFORMS
VM = 1.5V at VCC 2.7V ; VM = 0.5 VCC at VCC 2.7V; VOL and
VOH are the typical output voltage drop that occur with the output
load.
tW
tW
trt
tW
tW
tW
nB INPUT
nA INPUT
nQ OUTPUT
SV00139
Figure 1.Output pulse control using retrigger pulse;
nRD = HIGH.
tW
tW
tW
nB INPUT
nRD INPUT
nQ OUTPUT
SV00140
Figure 2.Output pulse control using reset input nRD;
nA = LOW.
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
1998 Apr 28 9
nB INPUT
(nA LOW)
tW
tW
tPLH
VM
VM
VM
tW
tTLH
tTHL
tPLH
tTHL
tTLH tPLH
tW
tPHL
tPHL
VM
tW
tPLH
nA INPUT
(nB HIGH)
nRD INPUT
Q OUTPUT
Q OUTPUT
SV00197
Figure 3. Input (nA, nB, nRD) to output (nQ, nQ) propagation delays, the output transition times,
and the input and output pulse widths.
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
1998 Apr 28 10
0.8
0.4
0024
VCC (V)
‘K’ factor
SV00185
136
5
Figure 4. HCT typical “k” factor as a function of VCC;
CX = 10 nF; RX = 10 KW to 100 KW.
0110
2
SV00141
10 103104
102
103
104
105
106
tW
ns
CEXT (pF)
REXT =
100kW
50kW
10kW
2kW
Figure 5.Typical output pulse width as a function of the
external capacitor values at VCC = 3.3V and Tamb = 25°C.
APPLICATION INFORMATION
Power-up considerations
When the monostable is powered-up it may produce an output
pulse, with a pulse width defined by the values of RX and CX. This
output pulse can be eliminated using the circuit shown in Figure 6.
SV00152
RXVCC
A
B
CX
Q
Q
RESET VCC
nCEXT nREXT/CEXT
“123”
Figure 6. Power-up output pulse elimination circuit
Power-down considerations
A large capacitor (CX) may cause problems when powering-down
the monostable due to the energy stored in this capacitor. When a
system containing this device is powered-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, connect a damping diode (DX) preferably a
germanium or Schottky type diode able to withstand large current
surges as shown in Figure 7.
VCC
DX
RX
CX
nREXT/CEXT
SV00154
Figure 7. Power-down protection circuit
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
1998 Apr 28 11
TEST CIRCUIT
PULSE
GENERATOR
RT
Vl
D.U.T.
VO
CLRL= 1k
Vcc
Test Circuit for Outputs
DEFINITIONS
VCC VI
< 2.7V
2.7–3.6V
VCC
2.7V
TEST
tPLH/tPHL
≥4.5 V VCC
RL = Load resistor
CL = Load capacitance includes jig and probe capacitiance
50pF
RT = Termination resistance should be equal to ZOUT of pulse generators.
SV00902
Figure 8. Load circuitry for switching times
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
1998 Apr 28 12
DIP16: plastic dual in-line package; 16 leads (300 mil); long body SOT38-1
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
1998 Apr 28 13
SO16: plastic small outline package; 16 leads; body width 3.9 mm SOT109-1
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
1998 Apr 28 14
SSOP16: plastic shrink small outline package; 16 leads; body width 5.3 mm SOT338-1
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
1998 Apr 28 15
TSSOP16: plastic thin shrink small outline package; 16 leads; body width 4.4 mm SOT403-1
Philips Semiconductors Product specification
74LV123
Dual retriggerable monostable multivibrator
with reset
1998 Apr 28 16
Philips Semiconductors and Philips Electronics North America Corporation reserve the right to make changes, without notice, in the products,
including circuits, standard cells, and/or software, described or contained herein in order to improve design and/or performance. Philips
Semiconductors assumes no responsibility or liability for the use of any of these products, conveys no license or title under any patent, copyright,
or mask work right to these products, and makes no representations or warranties that these products are free from patent, copyright, or mask
work right infringement, unless otherwise specified. Applications that are described herein for any of these products are for illustrative purposes
only. Philips Semiconductors makes no representation or warranty that such applications will be suitable for the specified use without further testing
or modification.
LIFE SUPPORT APPLICATIONS
Philips Semiconductors and Philips Electronics North America Corporation Products are not designed for use in life support appl iances, devices,
or systems where malfunction of a Philips Semiconductors and Philips Electronics North America Corporation Product can reasonably be expected
to result in a personal injury. Philips Semiconductors and Philips Electronics North America Corporation customers using or selling Philips
Semiconductors and Philips Electronics North America Corporation Products for use in such applications do so at their own risk and agree to fully
indemnify Philips Semiconductors and Philips Electronics North America Corporation for any damages resulting from such improper use or sale.
This data sheet contains preliminary data, and supplementary data will be published at a later date. Philips
Semiconductors reserves the right to make changes at any time without notice in order to improve design
and supply the best possible product.
Philips Semiconductors
811 East Arques Avenue
P.O. Box 3409
Sunnyvale, California 94088–3409
Telephone 800-234-7381
DEFINITIONS
Data Sheet Identification Product Status Definition
Objective Specification
Preliminary Specification
Product Specification
Formative or in Design
Preproduction Product
Full Production
This data sheet contains the design target or goal specifications for product development. Specifications
may change in any manner without notice.
This data sheet contains Final Specifications. Philips Semiconductors reserves the right to make changes
at any time without notice, in order to improve design and supply the best possible product.
Copyright Philips Electronics North America Corporation 1998
All rights reserved. Printed in U.S.A.
print code Date of release: 05-96
Document order number: 9397-750-04418
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