Flicker noise: Difference between revisions
→See also: «"Shot noise]] * Burst noise * Thermal noise * [[Avalanche" → "Electronic"» |
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'''Flicker noise''' is a type of [[electronic noise]] with a 1/f, or [[pink noise|pink]] spectrum. It is therefore often referred to as '''1/f noise''' or '''pink noise''', though these terms have wider definitions. It occurs in almost all [[electronic device]]s, and results from a variety of effects, such as impurities in a conductive channel, generation and [[recombination]] noise in a [[transistor]] due to base current, and so on. It is always related to a [[direct current]]. |
'''Flicker noise''' is a type of [[electronic noise]] with a 1/f, or [[pink noise|pink]] spectrum. It is therefore often referred to as '''1/f noise''' or '''pink noise''', though these terms have wider definitions. It occurs in almost all [[electronic device]]s, and results from a variety of effects, such as impurities in a conductive channel, generation and [[recombination]] noise in a [[transistor]] due to base current, and so on. It is always related to a [[direct current]]. |
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In electronic devices, it is a low-frequency phenomenon, as the higher frequencies are overshadowed by [[white noise]] from other sources. Flicker noise is often characterized by the [[corner frequency]] between the regions dominated by each type |
In electronic devices, it is a low-frequency phenomenon, as the higher frequencies are overshadowed by [[white noise]] from other sources. Flicker noise is often characterized by the [[corner frequency]] <math>f_c</math> between the regions dominated by each type. [[MOSFET|MOSFETs]] have a higher <math>f_c</math> than [[JFET|JFETs]] or [[bipolar_transistor|bipolar transistors]] which is usually below 2 [[kHz]] for the later. |
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Flicker noise is found in [[carbon]] composition [[resistor]]s, where it is referred to as ''excess noise'', since it increases the overall noise level above the [[thermal noise]] level, which is present in all resistors. In contrast, wire-wound resistors have the least amount of flicker noise. Since flicker noise is related to the level of DC, if the current is kept low, thermal noise will be the predominant effect in the resistor, and the type of resistor used will not affect noise levels. |
Flicker noise is found in [[carbon]] composition [[resistor]]s, where it is referred to as ''excess noise'', since it increases the overall noise level above the [[thermal noise]] level, which is present in all resistors. In contrast, wire-wound resistors have the least amount of flicker noise. Since flicker noise is related to the level of DC, if the current is kept low, thermal noise will be the predominant effect in the resistor, and the type of resistor used will not affect noise levels. |
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Revision as of 10:31, 12 December 2006
Flicker noise is a type of electronic noise with a 1/f, or pink spectrum. It is therefore often referred to as 1/f noise or pink noise, though these terms have wider definitions. It occurs in almost all electronic devices, and results from a variety of effects, such as impurities in a conductive channel, generation and recombination noise in a transistor due to base current, and so on. It is always related to a direct current.
In electronic devices, it is a low-frequency phenomenon, as the higher frequencies are overshadowed by white noise from other sources. Flicker noise is often characterized by the corner frequency between the regions dominated by each type. MOSFETs have a higher than JFETs or bipolar transistors which is usually below 2 kHz for the later.
Flicker noise is found in carbon composition resistors, where it is referred to as excess noise, since it increases the overall noise level above the thermal noise level, which is present in all resistors. In contrast, wire-wound resistors have the least amount of flicker noise. Since flicker noise is related to the level of DC, if the current is kept low, thermal noise will be the predominant effect in the resistor, and the type of resistor used will not affect noise levels.