SN74LS122D

Due to market price fluctuations, if you need to purchase or consult the price. You can contact us or emial to us:   sales@allicdata.com

Logic-Multivibrators are a type of digital circuit that can provide either logical or oscillatory output with classical ripple or astable characteristics. The SN74LS122D is one such device, and is used for applications such as pulse-width modulation, pulse-position modulation, and frequency division. This article will discuss the capabilities of the SN74LS122D, its application fields and its working principles.

Introduction to SN74LS122D

The SN74LS122D is a dual single-pole/single-throw (SPST) edge-triggered monostable/bistable Schmitt trigger multivibrator with retrigger inhibit. It has two independent on-chip Schmitt triggers that can be operated together as a dual-edge-triggered multivibrator, or separately as two independent single-output devices. The device is self-timed, with the trigger input establishing the timing. When either the A or B trigger input is pulsed, the opposite output is forced to the high level. The A and B trigger inputs are active low and the inhibit inputs are active high.

The SN74LS122D is pin-compatible with other twelve-pin dip-switch integrated circuits, enabling ease of use configuration. It is packaged in a standard pin-out configuration and is made from a polysilicon overlay technology, providing functionality with low power consumption and extremely high speed.

Application Field

The SN74LS122D is typically used in pulse-width modulation, pulse-position modulation and frequency division applications where a tightly defined pulse-width, pulse-position or division ratio is required. It can be used to generate an oscillatory output as a timer or frequency divider, or as a single logic output, as a clock-trigger source, a counter source, a frequency divider, or an astable multivibrator.

It is frequently used in automotive, industrial, and telecommunications applications such as in motor control, modems, and remote sensing systems. It can also be used in digital timing circuits and in computers, TV and stereo systems, and gaming devices.

Working Principle

The SN74LS122D works by employing a bistable or monostable circuit, called a Schmitt trigger. In a bistable circuit, the output is permanently HIGH or LOW and no input is required for the output to remain in use. In a monostable circuit, the output is LOW, but after an input is given the output will be HIGH for a predetermined length of time before returning to LOW.

The SN74LS122D uses an active-low triggering input, meaning that a negative or 0 V pulse is required to trigger the output. This results in an preset voltage level that is designated by the threshold of the Schmitt Trigger circuit in the device. When either the A or B trigger input is pulsed, the opposite output is forced to the high level.

The SN74LS122D also features an inhibit input, which when set HIGH, inhibits any output and the circuits remain in the LOW state, regardless of the input. With the inhibit input set to LOW, the outputs are allowed to be toggled by their respective trigger inputs.

Conclusion

The SN74LS122D is a valuable device in many applications, from automotive to remote sensing systems. Its unique packaging, low-power consumption and high speed make it an optimal solution for a variety of digital timing and frequency division needs. The device is self-timed, triggered by an active-low input, and includes a retrigger inhibit when the output is not wanted.

The specific data is subject to PDF, and the above content is for reference