Varying amplifier bias parameters to meet radio frequency (RF) communications requirements

摘要

The present invention relates to amplifier bias circuitry, which provides a direct current (DC) bias to a radio frequency (RF) amplifier. The amplifier bias circuitry includes a control loop having a control loop bandwidth, and an output impedance associated with providing the DC bias to the RF amplifier. The amplifier bias circuitry may vary the DC bias, the output impedance, the control loop bandwidth, or any combination thereof, to meet wireless communications requirements. For example, in a multi-mode radio, low output impedance may be needed to meet linearity requirements of the RF amplifier associated with wireless communications protocols in one mode of the multi-modes; however, some low output impedance designs may reduce the control loop bandwidth below that needed to meet modulation requirements associated with wireless communications protocols in another mode of the multi-modes.