Patent ID: 7586376

Claim:
A pre-power amplifier, comprising: A. load circuitry having an input, an output, and a connection to a first voltage supply lead, the load circuitry including an RF choke connected between the input and the first voltage supply lead, and a DC coupling capacitor connected between the input and the output; B. a switch array having a clock input, digital amplitude control inputs, an output connected with the input of the load circuitry, and connections with a second voltage supply lead, the switch array including arrays of transistors, each transistor having a source and a drain connected between the output and the second voltage supply lead and having a gate input coupled with the clock input and a digital amplitude control input, the switch array providing varying impedance to the input of the load circuitry; and C. compensation circuitry having control inputs, an output connected with the input of the load circuitry and connections with the second voltage supply, the compensation circuitry including a capacitor having one lead connected to the output of the compensation circuitry and another lead and an array of transistors, each transistor having a source and a drain connected between the other lead of the capacitor and the second voltage supply lead and a gate input connected with a control input.