NSC JM38510-01201BD, JM38510-01201BC Datasheet

TL/F/6538

54121/DM54121/DM74121 One-Shot with Clear and Complementary Outputs

June 1989

54121/DM54121/DM74121 One-Shot with
Clear and Complementary Outputs

General Description

The DM54/74121 is a monostable multivibrator featuring
both positive and negative edge triggering with complemen­tary outputs. An internal 2kX timing resistor is provided for
design convenience minimizing component count and lay­out problems. This device can be used with a single external
capacitor. Inputs (A) are active-low trigger transition inputs
and input (B) is an active-high transition Schmitt-trigger in­put that allows jitter-free triggering from inputs with tran­sition rates as slow as 1 volt/second. A high immunity to
V

CC

noise of typically 1.5V is also provided by internal cir-

cuitry at the input stage.

To obtain optimum and trouble free operation please read
operating rules and NSC one-shot application notes careful­ly and observe recommendations.

Features

Y

Triggered from active-high transition or active-low tran­sition inputs

Y

Variable pulse width from 30 ns to 28 seconds

Y

Jitter free Schmitt-trigger input

Y

Excellent noise immunity typically 1.2V

Y

Stable pulse width up to 90% duty cycle

Y

TTL, DTL compatible

Y

Compensated for VCCand temperature variations

Y

Input clamp diodes

Y

Alternate Military/Aerospace device (54121) is avail­able. Contact a National Semiconductor Sales Office/
Distributor for specifications.

Functional Description

The basic output pulse width is determined by selection of
an internal resistor R

INT

or an external resistor (RX) and

capacitor (C

X

). Once triggered the output pulse width is in­dependent of further transitions of the inputs and is a func­tion of the timing components. Pulse width can vary from a
few nano-seconds to 28 seconds by choosing appropriate
R

X

and CXcombinations. There are three trigger inputs from
the device, two negative edge-triggering (A) inputs, one pos­itive edge Schmitt-triggering (B) input.

Connection Diagram

Dual-In-Line Package

TL/F/6538– 1

Order Number 54121DMQB, 54121FMQB,

DM54121J, DM54121W or DM74121N

See NS Package Number J14A, N14A or W14B

Function Table

Inputs Outputs

A1 A2 B Q Q

LXHL H
XLH L H
XXL L H
HHX L H
H

v

HÉß

v

HHÉß

vv

H Éß

LX

u

Éß

XL

u

Éß

H

e

High Logic Level

L

e

Low Logic Level

X

e

Can Be Either Low or High

u

e

Positive Going Transition

v

e

Negative Going Transition

É

e

A Positive Pulse

ß

e

A Negative Pulse

C

1995 National Semiconductor Corporation RRD-B30M105/Printed in U. S. A.

Absolute Maximum Ratings (Note)

If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales
Office/Distributors for availability and specifications.

Supply Voltage 7V

Input Voltage 5.5V

Operating Free Air Temperature Range

DM54

b

55§Ctoa125§C

DM74 0

§

Ctoa70§C

Storage Temperature Range

b

65§Ctoa150§C

Note:

The ‘‘Absolute Maximum Ratings’’ are those values
beyond which the safety of the device cannot be guaran­teed. The device should not be operated at these limits. The
parametric values defined in the ‘‘Electrical Characteristics’’
table are not guaranteed at the absolute maximum ratings.
The ‘‘Recommended Operating Conditions’’ table will define
the conditions for actual device operation.

Recommended Operating Conditions

Symbol Parameter

DM54121 DM74121

Units

Min Nom Max Min Nom Max

V

CC

Supply Voltage 4.5 5 5.5 4.75 5 5.25 V

V

T

a

Positive-Going Input Threshold

1.4 2 1.4 2 V

Voltage at the A Input (V

CC

e

Min)

V

T

b

Negative-Going Input Threshold

0.8 1.4 0.8 1.4 V

Voltage at the A Input (V

CC

e

Min)

V

T

a

Positive-Going Input Threshold

1.5 2 1.5 2 V

Voltage at the B Input (V

CC

e

Min)

V

T

b

Negative-Going Input Threshold

0.8 1.3 0.8 1.3 V

Voltage at the B Input (V

CC

e

Min)

I

OH

High Level Output Current

b

0.4

b

0.4 mA

I

OL

Low Level Output Current 16 16 mA

t

W

Input Pulse Width (Note 1) 40 40 ns

dV/dt

Rate of Rise or Fall of

1 1 V/s

Schmidt Input (B) (Note 1)

dV/dt

Rate of Rise or Fall of

11V/ms

Logic Input (A) (Note 1)

R

EXT

External Timing Resistor (Note 1) 1.4 30 1.4 40 kX

C

EXT

External Timing Capacitance (Note 1) 0 1000 0 1000 mF

DC Duty Cycle (Note 1) R

T

e

2kX 67 67

%

R

T

e

R

EXT

(Max) 90 90

T

A

Free Air Operating Temperature

b

55 125 0 70

§

C

Note 1: T

A

e

25§C and V

CC

e

5V.

Electrical Characteristics over recommended operating free air temperature range (unless otherwise noted)

Symbol Parameter Conditions Min

Typ

Max Units

(Note 1)

V

I

Input Clamp Voltage V

CC

e

Min, I

I

eb

12 mA

b

1.5 V

V

OH

High Level Output V

CC

e

Min, I

OH

e

Max,

2.4 3.4 V

Voltage V

IL

e

Max, V

IH

e

Min

V

OL

Low Level Output V

CC

e

Min, I

OL

e

Max,

0.2 0.4 V

Voltage V

IH

e

Min, V

IL

e

Max

I

I

Input Current@Max V

CC

e

Max, V

I

e

5.5V
1mA

Input Voltage

I

IH

High Level Input V

CC

e

Max A1, A2 40

mA

Current V

I

e

2.4V
B80

I

IL

Low Level Input V

CC

e

Max A1, A2

b

1.6
mA

Current V

I

e

0.4V
B

b

3.2

I

OS

Short Circuit V

CC

e

Max DM54

b

20

b

55

mA

Output Current (Note 2)

DM74

b

18

b

55

I

CC

Supply Current V

CC

e

Max Quiescent 13 25

mA

Triggered 23 40

Note 1: All typicals are at V

CC

e

5V, T

A

e

25§C.

Note 2: Not more than one output should be shorted at a time.

2