Browse Definitions:
Definition

monostable circuit

Contributor(s): Stan Gibilisco

A monostable circuit is an electronic device called a multivibrator that has two distinct states, one of them stable (having a steady voltage) and the other one unstable (having an unsteady or variable voltage). Normally, the circuit is in the stable condition. The circuit can be removed from the stable condition temporarily by an input pulse called a triggering signal. After a certain period of time, which can be adjusted or set by choosing specific component values, the circuit returns to the stable state until another triggering signal is applied.

A monostable circuit comprises an IC (integrated circuit), usually a device called a 555 timer, along with an external resistance and an external capacitance. Normally, the voltage output equals zero or near zero. This state is called low. When a triggering pulse is applied to the input, the output voltage rises to the supply or battery voltage (the high state, which usually ranges from +3 to +15 volts) for a length of time that depends on the values of the resistance R and the capacitance C.

If we specify R in ohms and C in microfarads, then the pulse duration t, in microseconds, can be calculated as

 

t = 1.1 RC

This formula also applies for values of R in ohms, C in farads, and t in seconds.

After the delay time t has elapsed, the monostable circuit returns to the low state.

Monostable circuits are used as timers, pulse generators, waveform generators, and sweep generators for CRTs (cathode ray tubes) such as the ones found in some television (TV) receivers, older computer displays, oscilloscopes, and spectrum analyzers.

 

Continue reading about monostable circuits:

Tim Surtell describes the construction and operation of a simple monostable circuit using a 555 timer IC.

Computer Support Group offers a timeout calculator for monostable circuits based on the 555 timer IC.

This was last updated in April 2012

Start the conversation

Send me notifications when other members comment.

By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Please create a username to comment.

-ADS BY GOOGLE

File Extensions and File Formats

Powered by:

SearchCompliance

SearchSecurity

  • botnet

    A botnet is a collection of internet-connected devices, which may include PCs, servers, mobile devices and internet of things ...

  • Web application firewall (WAF)

    A Web application firewall (WAF) is a firewall that monitors, filters or blocks traffic to and from a Web application. WAFs are ...

  • MD5

    The MD5 hashing algorithm is a one-way cryptographic function that accepts a message of any length as input and returns as output...

SearchHealthIT

SearchDisasterRecovery

  • call tree

    A call tree -- sometimes referred to as a phone tree -- is a telecommunications chain for notifying specific individuals of an ...

  • mass notification system (MNS)

    A mass notification system is a platform that sends one-way messages to inform employees and the public of an emergency.

  • disaster recovery as a service (DRaaS)

    One approach to a strong disaster recovery plan is DRaaS, where companies offload data replication and restoration ...

SearchStorage

  • compact disc (CD)

    A compact disc is a portable storage medium that can be used for recording, storing and playing back audio, video and other data ...

  • secondary storage

    Secondary storage is used to protect inactive data written from a primary storage array to a nonvolatile tier of disk, flash or ...

  • VRAM (video ram)

    VRAM (video RAM) is a reference to any type of random access memory (RAM) used to store image data for a computer display.

SearchSolidStateStorage

  • SSD RAID (solid-state drive RAID)

    SSD RAID (solid-state drive RAID) is a methodology commonly used to protect data by distributing redundant data blocks across ...

  • Tier 0

    Tier 0 (tier zero) is a level of data storage that is faster, and perhaps more expensive, than any other level in the storage ...

  • PCIe SSD (PCIe solid-state drive)

    A PCIe SSD (PCIe solid-state drive) is a high-speed expansion card that attaches a computer to its peripherals.

SearchCloudStorage

  • RESTful API

    A RESTful application program interface breaks down a transaction to create a series of small modules, each of which addresses an...

  • cloud storage infrastructure

    Cloud storage infrastructure is the hardware and software framework that supports the computing requirements of a private or ...

  • Zadara VPSA and ZIOS

    Zadara Storage provides block, file or object storage with varying levels of compute and capacity through its ZIOS and VPSA ...

Close