A mobile communication terminal including a power amplifier configured to
amplify a power of a received signal and wirelessly transmit the
amplified signal through an antenna, a high power detector configured to
determine whether the amplified power of the signal exceeds a particular
critical range, a detected voltage level converter configured to convert
a voltage corresponding to the output power exceeding the critical range
into a voltage having a particular voltage level, and a varied driving
voltage output unit configured to vary the converted voltage and apply
the varied voltage to the power amplifier.