A power amplifier includes a two-dimensional matrix of NM active cells formed by stacking main terminals of multiple active cells in series. The stacks are coupled in parallel to form the two-dimensional matrix. The power amplifier includes a driver structure to coordinate the driving of the active cells so that the effective output power of the two-dimensional matrix is approximately NM the output power of each of the active cells.

Embodiments of RF amplifiers and packaged RF amplifier devices each include a transistor with a drain-source capacitance that is relatively low, an output impedance matching circuit, and a harmonic termination circuit. The impedance matching circuit includes a harmonic termination circuit, which includes a first inductance (a first plurality of bondwires) and a first capacitance coupled in series between the transistor output and a ground reference node. An equivalent capacitance from a combination of the first inductive element and the first capacitance in series effectively increases the drain-source capacitance by at least 10 percent. The impedance matching circuit also includes a second inductance (a second plurality of bondwires) and a second capacitance coupled in series between the transistor output and the ground reference node, where the second inductance and the second capacitance are directly connected. The first and second capacitances may be metal-insulator-metal capacitors in an integrated passive device.

A communications device includes a transmission chain coupled to an antenna a receiver chain coupled to the antenna. The receiver chain includes an amplifier device having an input coupled to the antenna. A controlled switching circuit is included in the amplifier device and is operable to selectively disconnect conduction terminals of an amplifying transistor from power supply terminals when the transmission chain is operating to pass a transmit signal to the antenna.

A power amplifier includes a two-dimensional matrix of NM active cells formed by stacking main terminals of multiple active cells in series. The stacks are coupled in parallel to form the two-dimensional matrix. The power amplifier includes a driver structure to coordinate the driving of the active cells so that the effective output power of the two-dimensional matrix is approximately NM the output power of each of the active cells.

An amplifier circuit for amplifying an input signal includes a transistor configured to receive the input voltage via an input port, and a second-harmonic trap connected between the transistor and ground, the second-harmonic trap having an impedance high enough to enable the second-harmonic trap to act as an open circuit at a second harmonic frequency of a voltage provided by the transistor. The second-harmonic trap includes a transformer including a primary winding connected to ground and a secondary winding, the primary winding receiving the voltage provided by the transistor. The second-harmonic trap further includes a variable capacitor connected in parallel with the secondary winding of the transformer, the variable capacitor having an adjustable capacitance that may be adjusted for the second-harmonic trap to act as the open circuit at the second harmonic frequency.

A power amplifier includes a two-dimensional matrix of NM active cells formed by stacking main terminals of multiple active cells in series. The stacks are coupled in parallel to form the two-dimensional matrix. The power amplifier includes a driver structure to coordinate the driving of the active cells so that the effective output power of the two-dimensional matrix is approximately NM the output power of each of the active cells.

Embodiments of an RF amplifier include a transistor with a control terminal and first and second current carrying terminals, and a shunt circuit coupled between the first current carrying terminal and a ground reference node. The shunt circuit is an output pre-match impedance conditioning shunt circuit, which includes a first shunt inductance, a second shunt inductance, and a shunt capacitor coupled in series. The first shunt inductance comprises a plurality of bondwires coupled between the first current carrying terminal and the second shunt inductance, and the second shunt inductance comprises an integrated inductor coupled between the first shunt inductance and a first terminal of the shunt capacitor. The shunt capacitor is configured to provide capacitive harmonic control of an output of the transistor.

Techniques for monitoring a distortion signal of a power amplifier circuit, where the output of a distortion monitoring circuit includes little or no fundamental signal and closely represents the actual distortion of the amplifier circuit of a wired communications system. The power amplifier circuit can generate a distortion feedback signal that does not affect the power amplifier's output power capability, e.g., no inherent loss in the fundamental output of the amplifier. That is, using a distortion monitor circuit, the power amplifier circuit can resolve a distortion feedback signal from the intended output signal of the output power amplifier circuit.

A low-noise amplifier device includes an inductive input element, an amplifier circuit, an inductive output element and an inductive degeneration element. The amplifier device is formed in and on a semiconductor substrate. The semiconductor substrate supports metallization levels of a back end of line structure. The metal lines of the inductive input element, inductive output element and inductive degeneration element are formed within one or more of the metallization levels. The inductive input element has a spiral shape and the an amplifier circuit, an inductive output element and an inductive degeneration element are located within the spiral shape.

An amplifier includes a semiconductor substrate. A first conductive feature partially covers the bottom substrate surface to define a conductor-less region of the bottom substrate surface. A first current conducting terminal of a transistor is electrically coupled to the first conductive feature. Second and third conductive features may be coupled to other regions of the bottom substrate surface. A first filter circuit includes an inductor formed over a portion of the top substrate surface that is directly opposite the conductor-less region. The first filter circuit may be electrically coupled between a second current conducting terminal of the transistor and the second conductive feature. A second filter circuit may be electrically coupled between a control terminal of the transistor and the third conductive feature. Conductive leads may be coupled to the second and third conductive features, or the second and third conductive features may be coupled to a printed circuit board.