Power Amplifier

What Does Power Amplifier Mean?

A power amplifier (PA) is defined by the ratio between the power supplied to the load and the power provided to the circuit by the source. A PA is categorized on the basis of its power rating, which is measured in watts (W). The power rating can be stated in terms of load impedance (ohm) across which the output power is measured.


Techopedia Explains Power Amplifier

Modern electronic circuits give high power amplification when low impedance is used (in the case of speakers), but this is not always recommended. Generally, the rated power output of an amplifier is said to be its peak output value. For example, if the PA is rated at 20 W, then the output can range from 0 to 20 (i.e., the maximum rated value). In the case of an overdriven input, the PA can give an output power that is many times higher than the maximum rated value, but, at the same time, the output signal quality decreases. Power amplifiers are used in a number of everyday appliances such as audio speakers and microwave ovens.


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Margaret Rouse

Margaret Rouse is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical, business audience. Over the past twenty years her explanations have appeared on TechTarget websites and she's been cited as an authority in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine and Discovery Magazine.Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages. If you have a suggestion for a new definition or how to improve a technical explanation, please email Margaret or contact her…