A radio frequency (RF) power combiner includes a first port with a first inverting input and a first non-inverting input, a second port with a second inverting input and a second non-inverting input, a first stabilization line coupled between the first non-inverting input and second non-inverting input, and a second stabilization line coupled between the first inverting input and the second inverting input.

A radio frequency (RF) power transistor circuit includes a power transistor and a decoupling circuit. The power transistor has a control electrode coupled to an input terminal for receiving an RF input signal, a first current electrode for providing an RF output signal at an output terminal, and a second current electrode coupled to a voltage reference. The decoupling circuit includes a first inductive element, a first resistor, and a first capacitor coupled together in series between the first current electrode of the power transistor and the voltage reference. The decoupling circuit is for dampening a resonance at a frequency lower than an RF frequency.

Systems, methods and apparatus for practical realization of an integrated circuit comprising a stack of transistors operating as an RF amplifier are described. As stack height is increased, capacitance values of gate capacitors used to provide a desired distribution of an RF voltage at the output of the amplifier across the stack may decrease to values approaching parasitic/stray capacitance values present in the integrated circuit which may render the practical realization of the integrated circuit difficult. Coupling of an RF gate voltage at the gate of one transistor of the stack to a gate of a different transistor of the stack can allow for an increase in the capacitance value of the gate capacitor of the different transistor for obtaining an RF voltage at the gate of the different transistor according to the desired distribution.

A push-pull dynamic amplifier is operable in reset and amplification phases. The amplifier includes first NMOS and PMOS input transistors that are electrically coupled to a first input terminal and a first output terminal. Second NMOS and PMOS input transistors are electrically coupled to a second input terminal and a second output terminal. First and second reset switches are electrically coupled to the first and second output terminals, respectively. A power supply switch is electrically coupled to the first and the second PMOS transistors, and a ground switch is electrically coupled to the first and the second NMOS transistors. During the reset phase, the reset switches are closed and the power supply switch and the ground switch are opened. During the amplification phase, the reset switches are opened and the power supply switch and the ground switch are closed.

A radio frequency (RF) power transistor circuit includes a power transistor and at least one decoupling circuit. The power transistor has a control electrode coupled to an input terminal for receiving an RF input signal, and a current electrode for providing an RF output signal at an output terminal. A decoupling circuit is coupled between the control electrode and a ground terminal, and/or between the current electrode and the ground terminal. The decoupling circuit includes a resistor coupled in series with components of a resonant circuit having a resonance that is lower than an RF frequency (e.g., lower than 20 megahertz). The resistor is for dampening the resonance of the resonant circuit.

An amplifier including a signal input terminal, at least one signal output terminal, a first and a second cascode amplifier circuits, a capacitor and a loading circuit. The signal input terminal receives an input signal. The first cascode amplifier circuit includes a first and a second input terminals and a first and a second output terminals. The first input terminal coupled to the signal input terminal receives the input signal. The second cascode amplifier circuit includes a third and a fourth input terminals and a third output terminal. The third input terminal is coupled to the first output terminal, and the third output terminal is coupled to the second input terminal. Two terminals of the capacitor are coupled to the fourth input terminal and the first output terminal respectively. A terminal of the loading circuit is coupled to the third output terminal, and another terminal of the loading circuit is coupled to the second output terminal. At least one of two terminals of the loading circuit is further coupled to the at least one signal output terminal.

In certain aspects, a multi-mode power amplifier includes first primary inductors, second primary inductors, and switches configured to selectively couple each of the second primary inductors with a respective one of the first primary inductors. The multi-mode power amplifier also includes power amplifiers coupled to the first primary inductors, and a secondary inductor magnetically coupled to the first primary inductors.

Embodiments provide an amplification circuit, an apparatus for amplifying, a low noise amplifier, a radio receiver, a mobile terminal, a base station, and a method for amplifying. An amplification circuit for amplifying a radio signal comprises a first amplification stage configured to amplify an input signal, V.sub.in(t), to obtain an intermediate signal. The amplification circuit further comprises a cascoding circuit configured to amplify the intermediate signal to obtain a first output signal V.sub.outn(t). The amplification circuit further comprises a second amplification stage configured to amplify the intermediate signal to obtain a second output signal, V.sub.outp(t).

High-frequency amplifier circuitry includes first amplifier circuitry, second amplifier circuitry, and noise figure improving circuitry. The first amplifier circuitry includes a first transistor and a grounded-gate third transistor. The first transistor has a source grounded via a first source inductor and a gate to which an input signal is applied. The third transistor is configured to output from a drain a signal obtained by amplifying a signal outputted from a drain of the first transistor. The second amplifier circuitry includes a same circuit constant as a circuit constant of the first amplifier circuitry and includes a second transistor and a grounded-gate fourth transistor. The noise figure improving circuitry connects the source of the first transistor and the source of the second transistor to each other.

Embodiments of a power amplifier and method of operating a power amplifier are disclosed. In one embodiment, a power amplifier includes a pulse wave modulation (PWM) controller, a first power control stage configured to drive a first output between VDD and VSS in response to a control signal from the PWM controller, a second power control stage configured to drive a second output between VDD and VSS in response to a control signal from the PWM controller, and a mid-voltage control circuit configured to hold the voltage of the first output at a mid-voltage that is between VDD and VSS during an interval between when the first output is driven between VDD and VSS and hold the voltage of the second output at the mid-voltage during an interval between when the first output is driven between VDD and VSS.