Systems and Methods for Providing Modulation of Switchmode RF Power Amplifiers

摘要

Systems and methods are provided for generating an amplitude modulation signal to a switchmode power amplifier. A DC to DC switch is configured to receive a DC input voltage and to provide a DC output voltage. A low dropout regulator is configured to provide the amplitude modulation signal according to a modulation control signal received by the low dropout regulator. A control circuit is configured to establish a nominal operating power level for the power amplifier via the amplitude modulation signal and to maintain a minimum voltage difference between the DC output voltage and the low dropout regulator output. A modulator control circuit is configured to provide the modulation control signal to the low dropout regulator. The modulator control circuit provides the transition from a high amplitude to a low amplitude and a transition from the low amplitude to the high amplitude at configurable first and second slopes, respectively.

主权项

1. An apparatus for generating an amplitude modulation signal, comprising:
a modulator control circuit configured to generate a modulation control signal and to selectively configure parameters of the modulation control signal to comply with a spectral mask; and a low dropout regulator configured to receive the modulation control signal from the modulator control circuit and to provide the amplitude modulation signal according to the modulation control signal.