Patent ID: 6166596
Filing Date: 2000-12-26
Classification: H03F

Abstract:
A high efficiency power amplifying apparatus for power amplifying an input signal applied to a signal input terminal, comprising:a PWM power amplifier for power amplifying an input signal from a signal input terminal by pulse width modulation;a passive low-pass filter for demodulating and outputting a pulse width modulated signal output from the PWM power amplifier;a positive floating voltage source for shifting a demodulated signal output from the passive low-pass filter a specific voltage +DV, and supplying a forward current;a negative floating voltage source for shifting a demodulated signal output from the passive low-pass filter a specific voltage -DV, and supplying a reverse current;a phase compensation circuit for phase compensating an input signal applied from the signal input terminal;a linear voltage amplifier comprising a linear circuit for voltage amplifying a signal phase compensated by the phase compensation circuit, shifting the amplified signal a specific voltage +dV and -dV, and outputting the shifted amplified signals; andan output device for current amplifying the +dV shifted voltage amplified signal by said forward current to generate a forward current amplified signal,current amplifying a -dV shifted voltage amplified signal by said reverse current to generate a reverse current amplified signal, andapplying said forward current amplified signal and reverse current amplified signal in a push-pull fashion to generate a power amplified signal.