Patent ID: 6975166

Claim:
A power amplifier comprising: a RF power amplifying unit ( 110 ) for generating a RF output signal by amplifying a received RF input signal; an envelope detector ( 120 ) for generating an envelope signal representing the envelope of said RF input signal; and a first DC/DC converter ( 130 ) for providing a supply voltage VccDy for said RF power amplifying unit ( 110 ) in response to said envelope signal; characterized in that the power amplifier further comprises: a second DC/DC converter ( 140 ) for generating a variety of n+1 voltage levels (V 1 . . . Vn+1) and n threshold values (T 1 . . . Tn) both in response to a received power control signal representing a required output power of the RF output signal of the RF power amplifying unit ( 110 ); the first DC/DC converter ( 130 ) conceived to select one of said n+1 voltage levels (V 1 . . . Vn+1) as said supply voltage for said RF power amplifying unit ( 110 ) in response to a comparison between the envelope signal and said n threshold values (T 1 . . . Tn).