Patent ID: 8331486
Filing Date: 2012-12-11
Classification: H03F,H03G

Abstract:
1. A transmitter circuit with output power control comprising: a buffer amplifier stage having an input and an output; a switching-mode power amplifier stage having an input coupled to said output of said buffer amplifier and having a power output; a DAC having digital input and an analog output; an inductor coupling said analog output of said DAC to said switching-mode power amplifier stage, whereby a power level at said power output is controlled by said digital input to said DAC; and a signal source coupled to said input of said buffer amplifier and a bypass capacitor coupling said analog output of said DAC to ground; wherein said input of said power amplifier stage comprises a gate of a MOSFET a source of said MOSFET is coupled to ground, and a drain of said MOSFET is coupled to said inductor said analog output of said DAC is a non-linear function of said digital input, and said analog output of said DAC is an exponential function of said digital input; wherein said exponential function is substantially: where PA