Active components are limited
to the amount of power that can be provided. When operating
within the linear region of the component, gain through the
component is constant for a given frequency. As the input signal
is increased in power, a point is reached where the power of the
signal at the output is not amplified by the same amount as the
smaller signal. At the point where the input signal is amplified
by an amount 1 dB less than the small signal gain, the 1 dB
Compression Point has been reached. A rapid decrease in gain
will be experienced after the 1 dB compression point is reached.
If the input power is increased to an extreme value, the
component will be destroyed.
nonlinear components such as diodes also exhibit 1 dB
compression points. Indeed, it is the nonlinear active
transistors that cause the 1 dB compression point to exist
in amplifiers. Of course, a power level can be reached in any
device that will eventually destroy it.