Philips 74lv423 DATASHEETS

INTEGRATED CIRCUITS

74LV423

Dual retriggerable monostable
multivibrator with reset

Product specification 1997 Feb 04
IC24 Data Handbook

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Philips Semiconductors Preliminary 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:

is used to determine the dynamic power dissipation (PD in µW)

1. C

PD

= CPD  V

P

D

= input frequency in MHz; CL = output load capacity in pF;

f

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

, nB to nQ, nQ

nA
nRD to nQ, nQ

Input capacitance 3.5 pF
Power dissipation capacitance per flip-flop VCC = 3.3V, VI = GND to V

2

 fi  (CL  V

2

 fo) where:

CC

)

DESCRIPTION

The 74LV423 is a low-voltage Si-gate CMOS device and is pin and
function compatible with the 74HC/HCT423.

The 74LV423 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 2 and 3 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 6. When C
width is defined as: t
t

W

C

EXT

nB inputs makes the circuit highly tolerant of slower input rise and
fall times.

CL = 15pF

= 3.3V

V

CC

= 5KΩ

R

EXT

= 0pF

C

EXT

74L V423

) and

). They are normally connected as shown in

EXT

) or the active HIGH-going edge input (nB). By repeating this

and C

EXT

= pulse width in ns; R

= 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

16
13

17 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 74LV423 N 74LV423 N SOT38-1
16-Pin Plastic SO –40°C to +125°C 74LV423 D 74LV423 D SOT109-1
16-Pin Plastic SSOP Type II –40°C to +125°C 74LV423 DB 74LV423 DB SOT338-1
16-Pin Plastic TSSOP Type I –40°C to +125°C 74L V423 PW 74LV423PW DH SOT403-1

1997 Feb 04 853–1913 17724

2

Philips Semiconductors Preliminary specification

Dual retriggerable monostable multivibrator
with reset

PIN CONFIGURATION

1A

1

1B

2

1R

3

D

1Q

4
5

2Q

6

2C

EXT

GND

7
8

2R

EXT/CEXT

PIN DESCRIPTION

PIN

NUMBER

1,9 1A, 2A

2,10 1B, 2B
3,11 1RD, 2RDDirect reset LOW

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)

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

&

V

16

CC

15

1R

EXT/CEXT

14

1C

EXT

13

1Q

12

2Q

11

2R

D

10

2B

9

2A

SV00096

13

4

5

12

LOGIC SYMBOL

1

1A
2A

9
2

1B

10

2B

3

1R

D

11

2R

D

FUNCTIONAL DIAGRAM

1

1A
2A

9

1B

2

2B

10

1R

3

D

2R

11

D

74L V423

14

1C

EXT

6

2C

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

15

7

1Q

13

2Q

5

1Q

4

2Q

12

SV00160

14

1C

EXT

2C

6

EXT

15

7

1Q

13

2Q

5

1Q

4

2Q

12

SV00162

1997 Feb 04

11

R

SV00161

3

Philips Semiconductors Preliminary specification

Dual retriggerable monostable multivibrator
with reset

LOGIC DIAGRAM

R

D

RR

CLCLV

CC

V

CC

CL

R

nR

V

CC

74L V423

EXT/CEXT

Q

Q

A

B

It is recommended that Pin 6 (2C

CLCL

) and Pin 14 (1C

EXT

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

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

C

EXT

to nC

EXT

(pin 14 or 6)

Figure 1. Timing Component Connection

V

CC

to nR

EXT/CEXT

(pin 15 or 7)

SV00163

R

EXT

SV00101

1997 Feb 04

4

Philips Semiconductors Preliminary specification

Dual retriggerable monostable multivibrator

74L V423

with reset

ABSOLUTE MAXIMUM RATINGS

In accordance with the Absolute Maximum Rating System (IEC 134).
Voltages are referenced to GND (ground = 0V).

SYMBOL

I

I

V

CC

DC supply voltage –0.5 to +7.0 V
DC input diode current VI < –0.5 or VI > VCC + 0.5V 20 mA

IK

DC output diode current VO < –0.5 or VO > VCC + 0.5V 50 mA

OK

DC output source or sink current

I

– standard outputs

O

– bus driver outputs
DC VCC or GND current for types with

I

,

I

T

GND

stg

– standard outputs
– bus driver outputs

CC

Storage temperature range –65 to +150 °C
Power dissipation per package

P

TOT

– plastic DIL
– plastic mini-pack (SO)
– plastic shrink mini-pack (SSOP and TSSOP)

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.

PARAMETER CONDITIONS RATING UNIT

1, 2

–0.5V < VO < VCC + 0.5V

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

25
35

50
70

750
500
500

mA

mA

mW

RECOMMENDED OPERATING CONDITIONS

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNIT

V

CC

V

V

T

amb

tr, t

NOTE:

1. The LV is guaranteed to function down to V

DC supply voltage See Note 1 1.2 3.3 5.5 V
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

= 1.0V (input levels GND or VCC); DC characteristics are guaranteed from VCC = 1.2V to VCC = 5.5V.

CC

See DC and AC

characteristics per device

VCC = 1.0V to 2.0V

= 2.0V to 2.7V

V

CC

= 2.7V to 3.6V

V

CC

= 3.6V to 5.5V

V

CC

–40
–40

–
–
–

–
–
–
–

CC
CC

+85

+125

500
200
100

50

V
V

°C

ns/V

1997 Feb 04

5