RADIO FREQUENCY SIGNAL POWER AMPLIFICATION CIRCUIT

摘要

An RF amplifier includes a branch with an inductor series-connected with a capacitor between first and second power supply nodes, a junction point between the inductor and capacitor forming an output node. A further branch includes a MOS transistor series-connected with a switch between the output node and the second power supply node. The switch has a control node coupled to receive a first input signal. The MOS transistor has a gate coupled to receive a second input signal. A control circuit applies the power supply voltage as the second input signal when a frequency/phase-modulated signal is applied as the first input signal. The control circuit further applies a variable signal as the second input signal when a radio frequency signal of constant frequency, phase, and amplitude is applied as the first input signal, and in this mode the MOS transistor is constrained to operate as a current source.

主权项

1. A radio frequency signal power amplifier, comprising:
a first branch comprising an inductor series-connected with a first capacitor between a first node and a second node of application of a direct current (DC) power supply voltage, wherein a junction point of the inductor and the first capacitor forms an output node of the amplifier that is configured to be coupled to a load; a second branch comprising a first MOS transistor series-connected with a first switch between the output node the second node, the first switch having a control node coupled to a first input node configured to receive a first input signal, the first MOS transistor having a gate coupled to a second input node configured to receive a second input signal; and a circuit configured to generate a binary signal indicative of a sign of a difference between a drain-source voltage of the first transistor and a gate-source voltage minus a threshold voltage of the first transistor.