The power bandwidth of an amplifier is sometimes taken as the frequency range (or, rarely, the upper frequency limit) for which the rated power output[1] of an amplifier can be maintained (without excessive distortion) to at least half of the full rated power.[2] [3] (Some specifications may mandate 100% of the rated power; sometimes referring to the full-power bandwidth.)
It should not be confused with "half-power" bandwidth, only used in conjunction with filter frequency response curves, where it refers to -3dB points in the frequency response of a band-pass filter.
Data sheets for operational amplifiers often use the term (full-)power bandwidth to indicate the highest frequency at which the achievable peak-to-peak output voltage swing is still equal to the DC output voltage range. This is also sometimes described as the slew-rate-limited bandwidth. The full-power bandwidth
BW
SR
Vamp
| BW= | SR |
| \pi~Vamp |
where
BW
Power bandwidth may be specified as a frequency limit or shown in the form of a graph (e.g. as maximum available voltage swing versus frequency, often with power supply voltage as a parameter).[4]