A radio frequency (RF) summer circuit having a characteristic impedance Zo comprises first and second ports coupled by first and second resistances, respectively, to a junction. The circuit further comprises a series combination of a third resistance and a switch movable between open and closed positions and an amplifier having input and output terminals and operable in an off state and an on state wherein the series combination is coupled across the input and output terminals of the amplifier between the junction and a third port. The first resistance, second resistance, and the third resistance are all substantially equal to Z.sub.0/3. Further, when the switch is moved to the closed position and the amplifier is switched to the off state a passive mode of operation is implemented and when the switch is moved to the open position and the amplifier is switched to the on state an active mode of operation is implemented. The RF summer circuit develops a summed signal at the third port equal to a sum of signals at the first and second ports modified by one of first and second gain values.

A radio frequency (RF) summer circuit having a characteristic impedance Zo comprises first and second ports coupled by first and second resistances, respectively, to a junction. The circuit further comprises a series combination of a third resistance and a switch movable between open and closed positions and an amplifier having input and output terminals and operable in an off state and an on state wherein the series combination is coupled across the input and output terminals of the amplifier between the junction and a third port. The first resistance, second resistance, and the third resistance are all substantially equal to Z.sub.0/3. Further, when the switch is moved to the closed position and the amplifier is switched to the off state a passive mode of operation is implemented and when the switch is moved to the open position and the amplifier is switched to the on state an active mode of operation is implemented. The RF summer circuit develops a summed signal at the third port equal to a sum of signals at the first and second ports modified by one of first and second gain values.

Systems and apparatuses are disclosed that include an RF generator configured to generate RF signals having a wavelength. Amplifiers are configured to receive and amplify the RF signals from the RF generator and are separated from each other by a separation distance in a range between about 0.2 times the wavelength and about 10.0 times the wavelength. A power management system is configured to control one or more of the amplifiers based on information received that is associated with the RF signals.

Systems and apparatuses are disclosed that include an RF generator configured to generate RF signals having a wavelength. Amplifiers are configured to receive and amplify the RF signals from the RF generator and are separated from each other by a separation distance in a range between about 0.2 times the wavelength and about 10.0 times the wavelength. A power management system is configured to control one or more of the amplifiers based on information received that is associated with the RF signals.

A radio-frequency module includes an integrated circuit (IC) device and an external inductor provided outside the IC device. The IC device includes a plurality of low-noise amplifiers, one or more inductors, and a switching circuit. The plurality of low-noise amplifiers includes a plurality of transistors in one to one correspondence. The one or more inductors are coupled to one or more of the plurality of transistors. Each inductor is coupled to the emitter or source of a corresponding one of the plurality of transistors. The switching circuit is coupled between the emitter or source of each of the plurality of transistors and the external inductor. The external inductor is coupled between the switching circuit and ground in series with each of the one or more inductors via the switching circuit.

A radio-frequency module includes an integrated circuit (IC) device and an external inductor provided outside the IC device. The IC device includes a plurality of low-noise amplifiers, one or more inductors, and a switching circuit. The plurality of low-noise amplifiers includes a plurality of transistors in one to one correspondence. The one or more inductors are coupled to one or more of the plurality of transistors. Each inductor is coupled to the emitter or source of a corresponding one of the plurality of transistors. The switching circuit is coupled between the emitter or source of each of the plurality of transistors and the external inductor. The external inductor is coupled between the switching circuit and ground in series with each of the one or more inductors via the switching circuit.

According to one aspect, an integrated circuit having a radio frequency amplifier includes at least two amplifier stages and an impedance matching device between two amplifier stages of the radio frequency amplifier. The matching device includes two lines which are coupled by electromagnetic induction. The first line is connected to an output of the first amplifier stage and the second line is connected to an input of the second amplifier stage.

According to one aspect, an integrated circuit having a radio frequency amplifier includes at least two amplifier stages and an impedance matching device between two amplifier stages of the radio frequency amplifier. The matching device includes two lines which are coupled by electromagnetic induction. The first line is connected to an output of the first amplifier stage and the second line is connected to an input of the second amplifier stage.

A radio frequency module includes: a module board that includes a first principal surface and a second principal surface on opposite sides of the module board; a power amplifier; and a first circuit component. The power amplifier includes: a first amplifying circuit element; a second amplifying circuit element; and an output transformer that includes a primary coil and a secondary coil. An end of the primary coil is connected to an output terminal of the first amplifying circuit element. Another end of the primary coil is connected to an output terminal of the second amplifying circuit element. An end of the secondary coil is connected to an output terminal of the power amplifier. The first amplifying circuit element and the second amplifying circuit element are disposed on the first principal surface. The first circuit component is disposed on the second principal surface.

A dc coupled amplifier includes a pre-driver, and amplifier and a bias control circuit. The pre-driver is configured to receive one or more input signals and amplify the one or more input signals to create one or more pre-amplified signals. The amplifier has cascode configured transistors configured to receive and amplify the one or more pre-amplified signals to create one or more amplified signals, the amplifier further having an output driver termination element. The bias control circuit is connected between the pre-driver and the amplifier, the bias control circuit receiving at least one bias current from the output driver termination element of the amplifier, wherein the pre-driver, the amplifier and the bias control circuit are all formed on a same die.