Hybrid switched mode/linear power amplifier power supply for use in polar transmitter

A radio frequency (RF) transmitter (TX) for coupling to an antenna, said TX having a polar architecture comprised of an amplitude modulation (AM) path coupled to a power supply of a power amplifier (PA) and a phase modulation (PM) path coupled to an input of the PA, where said power supply comprises a switch mode stage for coupling between a power source and the PA, the switch mode stage providing x amount of output power, said power supply further comprising at least one linear mode stage coupled in parallel with the switch mode stage between the power source and the PA, the linear mode stage providing y amount of output power, where x is greater than y, and the ratio of x to y is optimized for particular application constraints, further comprising at least one auxiliary inductance coupled between an output of the switch mode stage and an output of the at least one linear mode stage.

A method to operate a radio frequency (RF) transmitter (TX), where the TX has a polar architecture comprised of an amplitude modulation (AM) path coupled to a power supply of a power amplifier (PA) and a phase modulation (PM) path coupled to an input of the PA, comprising:

• providing the power supply so as to comprise a switch mode part for coupling between a power source and the PA, the switch mode part providing x amount of output power;
• and
• coupling a linear mode part in parallel with the switch mode part between the power source and the PA, the linear mode part providing y amount of output power, where x is greater than y, and the ratio of x to y is optimized for particular application constraints, and where the linear mode part exhibits a faster response time to a required change in output voltage than the switch mode part.