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INTEGRATED CIRCUITS
74LV123
Dual retriggerable monostable
multivibrator with reset
Product specification
Supersedes data of 1997 Feb 04
IC24 Data Handbook
1998 Apr 20
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Philips Semiconductors Product specification
Dual retriggerable monostable multivibrator
with reset
FEA TURES
•Optimized for Low Voltage applications: 1.0 to 5.5V
•Accepts TTL input levels between V
•Typical V
T
amb
•Typical V
T
amb
(output ground bounce) 0.8V @ VCC = 3.3V,
OLP
= 25°C
(output VOH undershoot) 2V @ VCC = 3.3V,
OHV
= 25°C
= 2.7V and VCC = 3.6V
CC
•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 nR
•I
category: MSI
CC
EXT/CEXT
QUICK REFERENCE DATA
GND = 0V; T
SYMBOL
t
PHL/tPLH
C
I
C
PD
NOTES:
1. C
is used to determine the dynamic power dissipation (PD in µW)
PD
= CPD V
P
D
f
= input frequency in MHz; CL = output load capacitance in pF;
i
= output frequency in MHz; VCC = supply voltage in V;
f
o
(C
= 25°C; tr = tf 2.5 ns
amb
CC
2
V
L
fo) = sum of the outputs.
CC
PARAMETER CONDITIONS TYPICAL UNIT
Propagation delay
nA, nB to nQ, nQ
nRD to nQ, nQ
Input capacitance 3.5 pF
Power dissipation capacitance per monost-
able
2
fi (CL V
2
fo) where:
CC
)
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 (R
capacitor (C
Figure 1. Once triggered, the basic output pulse width may be
extended by retriggering the gated active LOW-going edge input
(nA
process, the output pulse period (nQ = HIGH, nQ
made as long as desired. Alternatively, an output delay can be
terminated at any time by a LOW-going edge on input nR
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 R
see Figure 5. When C
width is defined as: t
t
= pulse width in ns; R
W
C
EXT
nB inputs makes the circuit highly tolerant of slower input rise and
fall times.
CL = 15pF
V
= 3.3V
CC
= 5KΩ
R
EXT
C
= 0pF
EXT
VCC = 3.3V, VI = GND to V
74L V123
) and
). They are normally connected as shown in
EXT
) or the active HIGH-going edge input (nB). By repeating this
and C
EXT
= external capacitor in pF. Schmitt-trigger action in the nA and
CC
. For pulse width when C
EXT
10,000pF, the typical output pulse
EXT
= 0.45 R
W
= external resistor in KΩ; and
EXT
1
C
EXT
25
20
60 pF
EXT
= LOW) can be
EXT
(typ.), where
EXT
, which
D
<10000pF,
ns
ns
ORDERING INFORMATION
PACKAGES TEMPERATURE RANGE OUTSIDE NORTH AMERICA NORTH AMERICA PKG. DWG. #
16-Pin Plastic DIL –40°C to +125°C 74LV123 N 74LV123 N SOT38-1
16-Pin Plastic SO –40°C to +125°C 74LV123 D 74LV123 D SOT109-1
16-Pin Plastic SSOP Type II –40°C to +125°C 74LV123 DB 74LV123 DB SOT338-1
16-Pin Plastic TSSOP Type I –40°C to +125°C 74L V123 PW 74LV123PW DH SOT403-1
1998 Apr 28 853–191 1 19290
2
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Philips Semiconductors Product specification
Dual retriggerable monostable multivibrator
with reset
PIN CONFIGURATION
SV00096
16
V
CC
15
1R
EXT/CEXT
14
1C
EXT
13
1Q
12
2Q
11
2R
D
10
2B
9
2A
13
4
5
12
1
1A
1B
2
1R
3
D
1Q
4
5
2Q
2C
6
EXT
GND
7
8
2R
EXT/CEXT
PIN DESCRIPTION
PIN
NUMBER
1,9 1A, 2A
2,10 1B, 2B
3,11 1RD, 2R
4, 12 1Q, 2Q Outputs (active LOW)
7 2R
8 GND Ground (0V)
13, 5 1Q, 2Q Outputs (active HIGH)
14, 6
15 1R
16 V
SYMBOL FUNCTION
Trigger inputs
(negative-edge triggered)
Trigger inputs
(positive-edge triggered)
Direct reset LOW and trigger action at
D
positive edge
EXT/CEXT
1C
EXT,
2C
EXT
EXT/CEXT
CC
External resistor/capacitor connection
External capacitor connection
External resistor/capacitor connection
Positive supply voltage
LOGIC SYMBOL (IEEE/IEC)
14
15
1
2
3
6
7
9
10
CX
RCX
&
R
CX
RCX
&
LOGIC SYMBOL
1A
1
9
2A
1B
2
2B
10
1R
3
D
11
2R
D
FUNCTIONAL DIAGRAM
1A
1
2A
9
1B
2
2B
10
1R
3
D
11
2R
D
74LV123
14
1C
EXT
2C
6
EXT
1R
EXT/CEXT
2R
EXT/CEXT
S
Q
T
Q
R
D
1R
EXT/CEXT
2R
EXT/CEXT
S
Q
T
Q
R
D
1Q
2Q
1Q
2Q
SV00097
1C
EXT
2C
EXT
1Q
2Q
1Q
2Q
SV00099
15
7
13
5
4
12
14
6
15
7
13
5
4
12
1998 Apr 28
11
R
SV00098
3
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Philips Semiconductors Product specification
Dual retriggerable monostable multivibrator
with reset
LOGIC DIAGRAM
R
D
RR
CLCLV
CC
V
CC
CL
R
nR
V
CC
74LV123
EXT/CEXT
Q
Q
A
B
R
It is recommended that Pin 6 (2C
) and Pin 14 (1C
EXT
CLCL
FUNCTION TABLE
INPUTS OUTPUTS
nR
D
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
nA nB nQ nQ
) by externally grounded to Pin 8 (GND)
EXT
to nC
(pin 14 or 6)
Figure 1.Timing component connection
EXT
SV00100
V
CC
R
EXT
C
EXT
to nR
EXT/CEXT
(pin 15 or 7)
SV00101
1998 Apr 28
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Philips Semiconductors Product specification
Dual retriggerable monostable multivibrator
74LV123
with reset
RECOMMENDED OPERATING CONDITIONS
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNIT
1
1.0 3.3 5.5 V
CC
CC
–40
–40
–
–
–
–
–
–
–
–
+85
+125
500
200
100
50
25
T
V
V
tr, t
CC
V
amb
DC supply voltage See Note
Input voltage 0 – V
I
Output voltage 0 – V
O
Operating ambient temperature range in free
air
Input rise and fall times except for
f
Schmitt-trigger inputs
NOTE:
1. The LV is guaranteed to function down to V
ABSOLUTE MAXIMUM RATINGS
= 1.0V (input levels GND or VCC); DC characteristics are guaranteed from VCC = 1.2V to VCC = 5.5V.
CC
1, 2
In accordance with the Absolute Maximum Rating System (IEC 134).
Voltages are referenced to GND (ground = 0V).
SYMBOL
V
CC
I
IK
I
OK
I
O
DC supply voltage –0.5 to +7.0 V
DC input diode current VI < –0.5 or VI > VCC + 0.5V 20 mA
DC output diode current VO < –0.5 or VO > VCC + 0.5V 50 mA
DC output source or sink current
– standard outputs
PARAMETER CONDITIONS RATING UNIT
–0.5V < VO < VCC + 0.5V
See DC and AC
characteristics
VCC = 1.0V to 2.0V
VCC = 2.0V to 2.7V
VCC = 2.7V to 3.6V
VCC = 3.6V to 5.5V
V
V
°C
ns/V
mA
I
I
P
GND
T
TOT
stg
DC VCC or GND current for types with
,
– standard outputs 50
CC
Storage temperature range –65 to +150 °C
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
mA
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.
1998 Apr 28
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