Abstract: Apparatus and methods for programmable low dropout (LDO) regulators for radio frequency (RF) electronics are provided herein. In certain configurations, an LDO regulator for generating a programmable output voltage includes a regulation field-effect transistor (FET) having a drain electrically connected to the LDO regulator's output, an error amplifier that controls a gate of the regulation FET, a feedback circuit that provides a feedback signal to an inverting input of the error amplifier, an output capacitor electrically connected to the LDO regulator's output, and an alternative discharge circuit. When the output voltage of the LDO regulator is programmed from a high voltage level to a low voltage level, the alternative discharge circuit activates to discharge the output capacitor to improve the LDO regulator's transient response.

Abstract: Apparatus and methods for programmable low dropout (LDO) regulators for radio frequency (RF) electronics are provided herein. In certain configurations, an LDO regulator for generating a programmable output voltage includes a regulation field-effect transistor (FET) having a drain electrically connected to the LDO regulator's output, an error amplifier that controls a gate of the regulation FET, a feedback circuit that provides a feedback signal to an inverting input of the error amplifier, an output capacitor electrically connected to the LDO regulator's output, and an alternative discharge circuit. When the output voltage of the LDO regulator is programmed from a high voltage level to a low voltage level, the alternative discharge circuit activates to discharge the output capacitor to improve the LDO regulator's transient response.

Abstract: Systems, devices and methods related to multi-band power amplifier. In some embodiments, a power amplifier module includes a power amplifier having an output stage and configured to receive a signal. The power amplifier module also includes a first programmable harmonic termination circuit in electrical communication with the output stage of the power amplifier. The first programmable harmonic termination circuit includes a first plurality of capacitors and a first plurality of switches, with at least one of the first plurality of capacitors being in electrical communication with at least one of the first plurality of switches. The power amplifier module further includes a controller configured to modify a configuration of the first plurality of switches of the first programmable harmonic termination circuit based at least in part on a second harmonic frequency of the signal.

Abstract: A power amplifier module that includes a power amplifier and a controller is presented herein. The power amplifier module may include a set of transistor stages and a plurality of bias circuits. At least one transistor stage from the set of transistor stages may be in electrical communication with a first bias circuit and a second bias circuit from the plurality of bias circuits. The first bias circuit can be configured to apply a first bias voltage to the at least one transistor stage and the second bias circuit can be configured to apply a second bias voltage to the at least one transistor stage. The controller may be configured to activate one of the first bias circuit and the second bias circuit.

Abstract: A power amplifier module that includes a power amplifier and a controller is presented herein. The power amplifier module may include a set of transistor stages and a plurality of bias circuits. At least one transistor stage from the set of transistor stages may be in electrical communication with a first bias circuit and a second bias circuit from the plurality of bias circuits. The first bias circuit can be configured to apply a first bias voltage to the at least one transistor stage and the second bias circuit can be configured to apply a second bias voltage to the at least one transistor stage. The controller may be configured to activate one of the first bias circuit and the second bias circuit.

Abstract: Disclosed are systems, circuits and methods related to controlling of a radio-frequency (RF) power amplifier (PA). In some embodiments, a PA control circuit can include a first circuit configured to generate a replica base current from a base current provided to the PA, with the replica base current being representative of a collector current of the PA scaled by a beta parameter. The PA control circuit can further include a second circuit configured to generate a beta-tracking reference current from a temperature-compensated voltage and a base resistance associated with the PA. The PA control circuit can further include a current steering circuit configured to receive the replica base current and the beta-tracking reference current and generate a proportional current to a clamping node of a base driver. In some embodiments, the replica base current can be obtained by a current-mode comparison of a finger-sensed current with a ramp current.

Abstract: A power amplifier module that includes a power amplifier and a controller is presented herein. The power amplifier module may include a set of transistor stages and a plurality of bias circuits. At least one transistor stage from the set of transistor stages may be in electrical communication with a first bias circuit and a second bias circuit from the plurality of bias circuits. The first bias circuit can be configured to apply a first bias voltage to the at least one transistor stage and the second bias circuit can be configured to apply a second bias voltage to the at least one transistor stage. The controller may be configured to activate one of the first bias circuit and the second bias circuit.

Abstract: Disclosed are systems, circuits and methods related to controlling of a radio-frequency (RF) power amplifier (PA). In some embodiments, a PA control circuit can include a first circuit configured to generate a replica base current from a base current provided to the PA, with the replica base current being representative of a collector current of the PA scaled by a beta parameter. The PA control circuit can further include a second circuit configured to generate a beta-tracking reference current from a temperature-compensated voltage and a base resistance associated with the PA. The PA control circuit can further include a current steering circuit configured to receive the replica base current and the beta-tracking reference current and generate a proportional current to a clamping node of a base driver. In some embodiments, the replica base current can be obtained by a current-mode comparison of a finger-sensed current with a ramp current.