The disclosed technology is related to a radio-frequency (RF) amplifier having a bypass circuit and a resonant structure to improve performance in a bypass mode (e.g., a low gain mode). The disclosed amplifiers have a resonant structure that effectively isolates an amplifier core from a bypass circuit. For example, in a bypass mode, the resonant structure is configured to create an open impedance looking into the amplifier core input. This effectively removes any loading from the amplifier core to the bypass circuit. The disclosed amplifiers with resonant structures improve linearity performance in bypass modes due at least in part to the open impedance to the amplifier core provided by the resonant structure.

A transistor device includes a transistor cell comprising a channel region, a gate runner that is electrically connected to a gate electrode on the channel region and physically separated from the gate electrode, and a harmonic termination circuit electrically connected to the gate runner between the gate electrode and an input terminal of the transistor device, the harmonic termination circuit configured to terminate signals at a harmonic frequency of a fundamental operating frequency of the transistor device.

Devices and methods for generating a bias voltage for a transceiver operating in time division multiplexing operation, and corresponding transceivers are provided. In this case, the bias voltage is controlled in guard intervals between transmission and reception of signals by the transceiver.

Devices and methods for generating a bias voltage for a transceiver operating in time division multiplexing operation, and corresponding transceivers are provided. In this case, the bias voltage is controlled in guard intervals between transmission and reception of signals by the transceiver.

Methods and apparatus for implementing a power efficient amplifier device through the use of a main (primary) and auxiliary (secondary) power amplifier are described. The primary and secondary amplifiers operate as current sources providing current to the load. Capacitance coupling is used to couple the primary and secondary amplifier outputs. In some embodiments the combination of primary and secondary amplifiers achieve high average efficiency over the operating range of the device in which the primary and secondary amplifiers are used in combination as an amplifier device. The amplifier device is well suited for implementation using CMOS technology, e.g., N-MOSFETs, and can be implemented in an integrated circuit space efficient manner that is well suited for supporting RF transmissions in the GHz frequency range, e.g., 30 GHz frequency range. The primary amplifier in some embodiments is a CLASS-AB or B amplifier and the secondary amplifier is a CLASS-C amplifier.

Power amplifiers and related methods are disclosed having configurable switched mode operation in a high-power mode of operation and a low-power mode of operation. The power amplifiers have a first cascode amplifier coupled to receive a positive differential input and a second cascode amplifier coupled to receive a negative differential input. The first and second cascode amplifiers include output stages and first/second input stages. The first input stages and the second input stages are enabled in a high-power mode of operation. The first input stages are disabled and the second input stages are enabled during a low-power mode of operation. For further embodiments, a switchable clamp operates in the low-power mode to clamp a voltage output for the second input stages. For further embodiments, the output stages are provided a variable voltage bias or are coupled to tunable capacitances that are varied between the low-power and high-power modes.

The present disclosure relates to single-ended-to-differential amplifiers and radio frequency receivers. One example single-ended-to-differential amplifier includes a first inverting amplifier, a second inverting amplifier, and a third inverting amplifier. Both an input end of the first inverting amplifier and an input end of the second inverting amplifier are coupled to an input end of the single-ended-to-differential amplifier, an output end of the first inverting amplifier is coupled to an input end of the third inverting amplifier, an output end of the second inverting amplifier is coupled to a first output end of the single-ended-to-differential amplifier, and an output end of the third inverting amplifier is coupled to a second output end of the single-ended-to-differential amplifier. An impedance element is coupled between the input end of the first inverting amplifier and the output end of the first inverting amplifier.

The present disclosure relates to single-ended-to-differential amplifiers and radio frequency receivers. One example single-ended-to-differential amplifier includes a first inverting amplifier, a second inverting amplifier, and a third inverting amplifier. Both an input end of the first inverting amplifier and an input end of the second inverting amplifier are coupled to an input end of the single-ended-to-differential amplifier, an output end of the first inverting amplifier is coupled to an input end of the third inverting amplifier, an output end of the second inverting amplifier is coupled to a first output end of the single-ended-to-differential amplifier, and an output end of the third inverting amplifier is coupled to a second output end of the single-ended-to-differential amplifier. An impedance element is coupled between the input end of the first inverting amplifier and the output end of the first inverting amplifier.

The present disclosure relates to a power amplifier circuit. The power amplifier circuit includes a voltage-controlled current source and a current mirror. The voltage-controlled current source is configured to receive a first voltage and to generate a first current. The current mirror is connected to the voltage-controlled current source and to generate a second current in response to the first current. The second current continuously changes from 0 mA to about 120 mA as the first voltage continuously changes from 0 V to about 1 V.

The present disclosure relates to a power amplifier circuit. The power amplifier circuit includes a voltage-controlled current source and a current mirror. The voltage-controlled current source is configured to receive a first voltage and to generate a first current. The current mirror is connected to the voltage-controlled current source and to generate a second current in response to the first current. The second current continuously changes from 0 mA to about 120 mA as the first voltage continuously changes from 0 V to about 1 V.