Patent ID: 6700444
Filing Date: 2004-03-02
Classification: H03F

Abstract:
A high power RF power amplifier suitable for use in a wireless communication basestation for amplifying an RF signal over a broad range of power comprising:a) a main amplifier comprising a lateral DMOS transistor for amplifying the RF signal over a first range of power and with a power saturation level below the maximum of the broad range of power, b) a plurality of auxiliary amplifiers comprising lateral DMOS transistors connected in parallel with the main amplifier, each of the auxiliary amplifiers being biased to sequentially provide an amplified output signal after the main amplifier approaches saturation, c) a signal splitter for splitting an input signal and applying the split input signal to the main amplifier and to the plurality of auxiliary amplifiers, the signal splitter including a quarter-wave transformer connected to the input of the main amplifier, and d) an output for receiving and combining amplified output signals from the main amplifier and from the plurality of auxiliary amplifiers, the output including a resistive load connected to the output of the main amplifier and connected to the output of each auxiliary amplifier through a quarter-wave transformer.