Patent ID: 7254164

Claim:
A radio frequency (RF) transceiver integrated circuit, comprising: a local oscillator that generates an RF local oscillation signal corresponding to an RF channel; a receiver section operably coupled to the local oscillator to receive the RF local oscillation signal, wherein the receiver section receives an incoming RF signal, and wherein the receiver section down-converts the incoming RF signal based upon the RF local oscillation signal to produce an incoming baseband signal; a transmitter section operably coupled to the local oscillator to receive the RF local oscillation signal, wherein the transmitter section receives an outgoing baseband signal, and wherein the transmitter section up-converts the outgoing baseband signal to produce an outgoing RF signal; wherein the local oscillator further comprises a phase locked loop that generates a phase locked loop oscillation signal that further comprising a multi-stage class AB transconductance block for producing a linearized transconductance current as a part of converting a voltage to a current in a mixing stage of the phase locked loop; and wherein the multi-stage class AB transconductance block further comprises: a first DC coupled transconductance stage comprising MOSFET amplification devices operably coupled to produce a first differential current from a differential input voltage based on a first bias voltage; a second DC coupled transconductance stage comprising MOSFET amplification devices operably coupled to produce a second differential current based on the differential input voltage and a second bias voltage; a third DC coupled transconductance stage comprising MOSFET amplification devices operably coupled to produce a third differential current based on the differential input voltage and a third bias voltage, wherein output current of the class AB transconductance block is a sum of the first differential current, the second differential current and the third differential current; and a resistor ladder operable as a biasing circuit operably coupled to produce the first bias voltage, the second bias voltage and the third bias voltage, wherein the first bias voltage is greater than the second bias voltage and wherein the second bias voltage is greater than the third bias voltage wherein each bias voltage for each of the transconductance stage is produced from an output end of a resistor of the resistor ladder.