A power amplifier circuit for a radio transceiver has a linear mode amplifier and a saturated (nonlinear) mode amplifier, a diplex matching circuit coupled to the linear mode amplifier for impedance matching and for separating transmitted signals in a plurality of frequency bands, a low pass matching circuit coupled to the output of the saturated mode amplifier and means for selectably placing the power amplifier circuit in a linear mode for or a saturated mode, corresponding to digital and analog modes of operation of the cellular telephone, respectively in linear or digital mode, the linear amplifier is biased in the on state and the saturated mode amplifier may be biased in the off state. Similarly, in the saturated or analog mode of operation, the saturated mode amplifier is biased in the on state and the linear amplifier may be biased in the off state. The amplifier circuit may include a switch or circuit, coupled to an output of the diplex matching circuit and the output of the low pass matching circuit, for selectably coupling the first diplex matching circuit output or the low pass matching circuit output to an output line when the amplifier circuit is selectably placed in linear mode or saturated mode, respectively.

Dual-band, dual-mode power amplifier

A bias circuit operable to supply a bias current to a first transistor includes: a second transistor having a collector terminal connected to a first power supply; a first resistance element having one end connected to an emitter terminal of the second transistor and having the other end connected to a base terminal of the first transistor; a second resistance element having one end connected to the emitter terminal of the second transistor and having the other end connected to ground potential; at least one third resistance element provided between a base terminal of the second transistor and a second power supply; and a plurality of temperature compensation circuits connected to the base terminal of the second transistor which are operable to control a base potential of the second transistor so that the potential falls as a temperature rises.

Radio frequency power amplifier

One aspect of this disclosure is a power amplifier module that includes a power amplifier configured to amplify a radio frequency (RF) signal and tantalum nitride terminated through wafer via. The power amplifier includes a heterojunction bipolar transistor and a p-type field effect transistor, in which a semiconductor portion of the p-type field effect transistor corresponds to a channel includes the same type of semiconductor material as a collector layer of the heterojunction bipolar transistor. A metal layer in the tantalum nitride terminated through wafer via is included in an electrical connection between the power amplifier on a front side of a substrate and a conductive layer on a back side of the substrate. Other embodiments of the module are provided along with related methods and components thereof.

Power amplifier modules including related systems, devices, and methods

A power amplifier circuit has a driver amplifier stage including a low band driver amplifier and a high band driver amplifier. A final amplifier stage includes a linear mode amplifier for amplifying digitally modulated signals and a saturated (nonlinear) mode amplifier for amplifying frequency modulated (analog) signals. A switching network interconnects the driver amplifier stage and the final amplifier stage. Depending on the desired mode of operation, an appropriate driver amplifier can be coupled to an appropriate final amplifier to most effectively and efficiently amplify analog or digital RF signals in either of a plurality of frequency bands. A matching circuit is coupled to the linear mode final amplifier for impedance matching and for separating D-AMPS (800 MHz band) and PCS (1900 MHz band) digital signals. A power impedance matching circuit is coupled to the output of the saturated mode final amplifier. In one embodiment, an isolator is coupled to the output of one or more of the low band or high band outputs of the duplex matching circuit. In the low band analog path, a duplexer is provided ahead of the coupling means for reducing the RF power requirements on the coupling means. The switching network and input filter stage may precede a driver amplifier stage.

Dual-band, dual-mode power amplifier with reduced power loss

Systems and methods for increasing the efficiency of direct current (DC) power to radio frequency (RF) power include a harmonic matching network that inhibits harmonic current flow for a number of harmonic frequencies The matching network includes a number of sections, where each section generates an impedance that resonates with the output capacitance at a harmonic frequency Each section of the matching network also creates a high impedance to the amplifier at the respective odd harmonic frequency

Harmonic matching network for a saturated amplifier

Power amplifier operating at a fixed frequency or a narrow bandwidth and based upon a non-linear gain element. The power amplifier includes a resonant circuit operably connected to the non-linear gain element, the circuit being resonant at a harmonic of substantially the band center frequency of the non-linear gain element and being arranged to dissipate energy resulting from harmonic generation by the non-linear gain element during signal amplification. In a particular aspect of the power amplifier, resonant circuits comprising inductor-capacitor harmonic trap circuits tuned to different harmonics are placed at both the input and the output of a gallium arsenide heterojunction bipolar transistor HBT providing the non-linear gain element.

Power amplifier with harmonically trapped heterojunction bipolar transistor

This invention relates to amplifiers preferably operating in a fixed frequency or narrow board regime. The amplifiers are typically Gallium Arsenide (GaAs) Heterojunction Bipolar Transistors (HBTs). Harmonic termination in the form of short and open circuits at the input and output can produce optimum collector efficiency with an associated power gain.

Glenn Collinson

Papers

Power amplifier with harmonically trapped heterojunction bipolar transistor

Improvements in or relating to amplifiers