Burst noise is a type of
electronic noise that occurs in semiconductors and ultra-thin gate oxide films. It is also called random telegraph noise (RTN), popcorn noise, impulse noise, bi-stable noise, or random telegraph signal (RTS) noise.
It consists of sudden step-like transitions between two or more discrete voltage or current levels, as high as several hundred
microvolts, at random and unpredictable times. Each shift in offset voltage or current often lasts from several milliseconds to seconds, and sounds like
popcorn
Popcorn (also called popped corn, popcorns, or pop-corn) is a variety of corn kernel which expands and puffs up when heated. The term also refers to the snack food produced by the expansion. It is one of the oldest snacks, with evidence of p ...
popping if hooked up to an audio speaker.
Burst noise was first observed in early
point contact diodes, then re-discovered during the commercialization of one of the first
semiconductor
A semiconductor is a material with electrical conductivity between that of a conductor and an insulator. Its conductivity can be modified by adding impurities (" doping") to its crystal structure. When two regions with different doping level ...
op-amps; the 709.
No single source of burst noise is theorized to explain all occurrences, however the most commonly invoked cause is the random trapping and release of
charge carrier
In solid state physics, a charge carrier is a particle or quasiparticle that is free to move, carrying an electric charge, especially the particles that carry electric charges in electrical conductors. Examples are electrons, ions and holes. ...
s at thin film interfaces or at defect sites in bulk
semiconductor
A semiconductor is a material with electrical conductivity between that of a conductor and an insulator. Its conductivity can be modified by adding impurities (" doping") to its crystal structure. When two regions with different doping level ...
crystal. In cases where these charges have a significant impact on transistor performance (such as under a MOS gate or in a bipolar base region), the output signal can be substantial. These defects can be caused by manufacturing processes, such as heavy
ion implantation
Ion implantation is a low-temperature process by which ions of one element are accelerated into a solid target, thereby changing the target's physical, chemical, or electrical properties. Ion implantation is used in semiconductor device fabrica ...
, or by unintentional side-effects such as surface contamination.
Individual op-amps can be screened for burst noise with peak detector circuits, to minimize the amount of noise in a specific application.
Burst noise is modeled mathematically by means of the
telegraph process, a Markovian continuous-time
stochastic process
In probability theory and related fields, a stochastic () or random process is a mathematical object usually defined as a family of random variables in a probability space, where the index of the family often has the interpretation of time. Sto ...
that jumps discontinuously between two distinct values.
See also
*
Atomic electron transition
In atomic physics and chemistry, an atomic electron transition (also called an atomic transition, quantum jump, or quantum leap) is an electron changing from one energy level to another within an atom or artificial atom. The time scale of a qua ...
*
Telegraph process
References
External links
A review of popcorn noise and smart filtering www.advsolned.com
{{Noise
Noise (electronics)