# Power bandwidth

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 ${\displaystyle BW}$ is then related to the slew rate ${\displaystyle SR}$ in volts per second and the voltage swing ${\displaystyle V_{amp}}$ by

${\displaystyle BW={\frac {SR}{2~\pi ~V_{amp}}}}$

where ${\displaystyle BW}$ is expressed in hertz. In data sheets for commonly available operational amplifiers, slew rate is usually given in volts per microsecond.

## Specifying power bandwidth

Power bandwidth may be specified as a frequency range or as a graph.[4]

## References

1. ^ Audio Power Amplifier Design Handbook by Douglas Self; page 22
2. ^
3. ^ The sound reinforcement handbook by Gary Davis, Ralph Jones; page 197
4. ^ "Archived copy" (PDF). Archived from the original (PDF) on 2009-12-28. Retrieved 2010-02-06. TDA1013B power amplifier IC specifications