Lydersen method: Difference between revisions
en>Nick Number m sp properties WP:TYPO |
en>Addbot m Bot: Migrating 1 interwiki links, now provided by Wikidata on d:q1878591 |
||
| Line 1: | Line 1: | ||
The | The '''input offset voltage''' (<math>V_{os}</math>) is a parameter defining the [[differential amplifier|differential]] DC [[voltage]] required between the inputs of an [[amplifier]], especially an [[operational amplifier]] (op-amp), to make the output zero (for voltage amplifiers, 0 [[volts]] with respect to ground or between differential outputs, depending on the output type).<ref>{{cite book |title=Fundamentals of Analog Circuits |last=Floyd |first=Thomas L. |coauthors=Buchla, David |year=1998 |publisher=[[Prentice Hall]] |isbn=0-13-836933-X |url=http://books.google.com/books?id=iu4LAAAACAAJ&d }}</ref> | ||
An ideal op-amp amplifies the differential input; if this input is 0 volts (i.e. both inputs are at the same voltage with respect to ground), the output should be zero. However, due to manufacturing process, the differential input transistors of real op-amps may not be exactly matched. This causes the output to be zero at a non-zero value of differential input, called the input offset voltage. | |||
Typical values for <math>V_{os}</math> are around 1 to 10mV for cheap commercial-grade op-amp [[integrated circuits]] (IC). This can be reduced to several microvolts if nulled using the IC's offset null pins or using higher-quality or laser-trimmed devices. However, the input offset voltage value may drift with temperature or age. [[Chopper amplifiers]] actively measure and compensate for the input offset voltage, and may be used when very low offset voltages are required. | |||
[[Input bias current]] and [[input offset current]] also affect the net offset voltage seen for a given amplifier. The voltage offset due to these currents, however, are separate from the input offset voltage parameter and is related to the impedance of the signal source and of the feedback and input impedance networks such as the two resistors used in the basic inverting and non-inverting amplifier configurations. [[FET]]-input op-amps tend to have lower input bias currents than [[bipolar junction transistor|bipolar]]-input op-amps, and hence incur less offset of this type. | |||
==External links== | |||
*[http://www.analog.com/static/imported-files/tutorials/MT-037.pdf Analog Devices tutorial on op-amp input offset voltage and mitigation techniques] | |||
==References== | |||
{{reflist}} | |||
[[Category:Electrical parameters]] | |||
{{electronics-stub}} | |||
normally input offset voltage is measured in the terms of input voltage applied at the non-inverting terminal to make output zero. | |||
Latest revision as of 05:08, 20 March 2013
The input offset voltage () is a parameter defining the differential DC voltage required between the inputs of an amplifier, especially an operational amplifier (op-amp), to make the output zero (for voltage amplifiers, 0 volts with respect to ground or between differential outputs, depending on the output type).[1]
An ideal op-amp amplifies the differential input; if this input is 0 volts (i.e. both inputs are at the same voltage with respect to ground), the output should be zero. However, due to manufacturing process, the differential input transistors of real op-amps may not be exactly matched. This causes the output to be zero at a non-zero value of differential input, called the input offset voltage.
Typical values for are around 1 to 10mV for cheap commercial-grade op-amp integrated circuits (IC). This can be reduced to several microvolts if nulled using the IC's offset null pins or using higher-quality or laser-trimmed devices. However, the input offset voltage value may drift with temperature or age. Chopper amplifiers actively measure and compensate for the input offset voltage, and may be used when very low offset voltages are required.
Input bias current and input offset current also affect the net offset voltage seen for a given amplifier. The voltage offset due to these currents, however, are separate from the input offset voltage parameter and is related to the impedance of the signal source and of the feedback and input impedance networks such as the two resistors used in the basic inverting and non-inverting amplifier configurations. FET-input op-amps tend to have lower input bias currents than bipolar-input op-amps, and hence incur less offset of this type.
External links
References
43 year old Petroleum Engineer Harry from Deep River, usually spends time with hobbies and interests like renting movies, property developers in singapore new condominium and vehicle racing. Constantly enjoys going to destinations like Camino Real de Tierra Adentro.
Template:Electronics-stub normally input offset voltage is measured in the terms of input voltage applied at the non-inverting terminal to make output zero.
- ↑ 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.
My blog: http://www.primaboinca.com/view_profile.php?userid=5889534