Product Summary

The SN74LS221N is a dual monostable multivibrator with schmitt. Each multivibrator of the SN74LS221N features a negative-transition-triggered input and a positive-transition-triggered input either of which can be used as an inhibit input. Pulse triggering occurs at a voltage level and is not related to the transition time of the input pulse. Schmitt-trigger input circuitry for B input allows jitter-free triggering for inputs as slow as 1 volt/ second, providing the circuit with excellent noise immunity. A high immunity to VCC noise is also provided by internal latching circuitry. Once triggered, the outputs are independent of further transitions of the inputs and are a function of the timing components. The output pulses of the SN74LS221N can be terminated by the overriding clear. Input pulse width may be of any duration relative to the output pulse width. Output pulse width may be varied from 35 nanoseconds to a maximum of 70 s by choosing appropriate timing components. With Rext = 2.0 kW and Cext = 0, a typical output pulse of 30 nanoseconds is achieved. Output rise and fall times are independent of pulse length.

Parametrics

SN74LS221N absolute maximum ratings: (1)VCC Supply Voltage: 5.5 V; (2)TA Operating Ambient Temperature Range: -55 to 125 ℃; (3)IOH Output Current — High: -0.4 mA; (4)IOL Output Current — Low: 8.0 mA; (5)ts Clear-Inactive-State Setup Time: 15 ns.

Features

SN74LS221N features: (1)SN54LS221 and SN74LS221 is a Dual Highly Stable One-Shot; (2)Overriding Clear Terminates Output Pulse; (3)Pin Out is Identical to SN54/74LS123.

Diagrams

SN74LS221N pin connection

Image Part No Mfg Description Data Sheet Download Pricing
(USD)
Quantity
SN74LS221N
SN74LS221N

Texas Instruments

Monostable Multivibrator Dual w/Schmitt-trgr inputs

Data Sheet

0-1: $0.69
1-25: $0.62
25-100: $0.55
100-250: $0.48
SN74LS221NE4
SN74LS221NE4

Texas Instruments

Monostable Multivibrator Dual w/Schmitt-trgr inputs

Data Sheet

0-1: $0.69
1-25: $0.62
25-100: $0.55
100-250: $0.48
SN74LS221NSRG4
SN74LS221NSRG4

Texas Instruments

Monostable Multivibrator Dual Monostable Multivibrators

Data Sheet

0-1390: $0.32
1390-2000: $0.30
2000-5000: $0.29
5000-10000: $0.28
SN74LS221NSRE4
SN74LS221NSRE4

Texas Instruments

Monostable Multivibrator Dual w/Schmitt-trgr inputs

Data Sheet

0-1390: $0.32
1390-2000: $0.30
2000-5000: $0.29
5000-10000: $0.28
SN74LS221NSR
SN74LS221NSR

Texas Instruments

Monostable Multivibrator Dual w/Schmitt-trgr inputs

Data Sheet

0-1390: $0.32
1390-2000: $0.30
2000-5000: $0.29
5000-10000: $0.28