Patent ID: 8331486

Claim:
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: PA VDD =ke qn where PA VDD is a D.C. voltage on said drain of said MOSFET, k and q are constants and n is a number of significant bits input into said DAC.