Patent ID: 6300835
Filing Date: 2001-10-09
Classification: H03F

Abstract:
A power amplifier core having an input port and an output port for amplifying an RF signal, comprising:a first FET cell string for amplifying the RF signal, comprising at least two FET cells connected in series with the output port;a bias network coupled between the input port and the at least two FET cells for coupling the RF signal to the at least two FET cells, wherein the bias network provides a DC bias to the at least two FET cells and AC couples the RF signal to the at least two FET cells provided the DC biased such that the first FET cell string amplifies the RF signal;the bias network including:a bias capacitor coupled to the input port for AC coupling the RF signal to an associated FET cell;a resistor network coupled from the bias capacitor to the associated FET cell for providing the DC bias to the associated FET cell, wherein the DC bias is selected such that the associated FET cell amplifies the RF signal coupled through the bias capacitor; andthe resistor network including an upper resistor connected from the output port to a bias resistor string and a lower resistor connected from the bias resistor string to a bias voltage port, the bias resistor string including a bias resistor associated with each of the at least two FET cells.