A peak detector includes an asymmetrical latch having a first input and a second input; and a CMOS converter having a first input coupled to a first output of the asymmetrical latch, a second input coupled to a second output of the asymmetrical latch, and an output.

A reconfigurable amplifier includes a first transistor having a gate coupled to an input of the reconfigurable amplifier, and a source coupled to a ground. The reconfigurable amplifier also includes a gate control circuit, and a second transistor having a gate coupled to the gate control circuit, a source coupled to a drain of the first transistor, and a drain coupled to an output of the reconfigurable amplifier, wherein the gate control circuit is configured to output a bias voltage to the gate of the second transistor in a cascode mode, and output a switch voltage to the gate of the second transistor in a non-cascode mode. The reconfigurable amplifier further includes a load coupled to the output of the reconfigurable amplifier.

A radio frequency (RF) receive circuit is described herein. In accordance with one embodiment, the RF receive circuit includes a mixer configured to receive an RF input signal to down-convert the RF input signal into a base-band or intermediate frequency (IF) band, an analog-to-digital converter (ADC), and a signal processing chain coupled between the mixer and the ADC. The signal processing chain includes at least two circuit nodes. The RF receive circuit further includes an oscillator circuit that is configured to generate a test signal. The oscillator circuit is coupled to the signal processing chain and is configured to selectively feed the oscillator signal into one of the at least two circuit nodes.

A package or a chip including a linear amplifier and a power amplifier is provided, wherein the linear amplifier is configured to receive an envelope tracking signal to generate an amplified envelope tracking signal, the power amplifier is supplied by an envelope tracking supply voltage comprising a DC supply voltage and the amplified envelope tracking signal, and the power amplifier is configured to receive an input signal to generate an output signal.

A semiconductor die comprises a first active device, at least one of a second active device and a passive component, and electromagnetic shielding configured to at least partially electromagnetically isolate the first active device from the at least one of the second active device and the passive component. The electromagnetic shielding includes one of a grounded metal layer and via stack, and a grounded metal layer disposed one of above and below the first active device.

A packaged RF amplifier device includes input and output leads and a transistor die. The transistor die includes a transistor with a drain-source capacitance below 0.1 picofarads per watt. The device also includes a conductive connection between the transistor output terminal and the output lead, and a baseband termination circuit between the transistor output terminal and a ground reference node. The baseband termination circuit presents a low impedance to signal energy at envelope frequencies and a high impedance to signal energy at RF frequencies. The baseband termination circuit includes an inductive element, a resistor, and a capacitor connected in series between the transistor output terminal and the ground reference node. Except for a minimal impedance transformation associated with the conductive connection, the device is unmatched between the transistor output terminal and the output lead by being devoid of impedance matching circuitry between the transistor output terminal and the output lead.

A packaged RF amplifier device includes input and output leads and a transistor die. The transistor die includes a transistor with a drain-source capacitance below 0.1 picofarads per watt. The device also includes a conductive connection between the transistor output terminal and the output lead, and a baseband termination circuit between the transistor output terminal and a ground reference node. The baseband termination circuit presents a low impedance to signal energy at envelope frequencies and a high impedance to signal energy at RF frequencies. The baseband termination circuit includes an inductive element, a resistor, and a capacitor connected in series between the transistor output terminal and the ground reference node. Except for a minimal impedance transformation associated with the conductive connection, the device is unmatched between the transistor output terminal and the output lead by being devoid of impedance matching circuitry between the transistor output terminal and the output lead.

Doherty power amplifiers and devices are described with a low voltage driver stage in a carrier-path and a high voltage driver stage in a peaking-path. In an embodiment a Doherty power amplifier has a carrier-path driver stage transistor configured to operate using a first bias voltage at the driver stage output, and a final stage transistor configured to operate using a second bias voltage at the final stage output. A peaking-path driver stage transistor is configured to operate using a third bias voltage at the driver stage output, and a final stage transistor electrically coupled to the driver stage output of the peaking-path driver stage transistor is configured to operate using a fourth bias voltage at the final stage output, wherein the third bias voltage is at least twice as large as the first bias voltage.

Doherty power amplifiers and devices are described with a low voltage driver stage in a carrier-path and a high voltage driver stage in a peaking-path. In an embodiment a Doherty power amplifier has a carrier-path driver stage transistor configured to operate using a first bias voltage at the driver stage output, and a final stage transistor configured to operate using a second bias voltage at the final stage output. A peaking-path driver stage transistor is configured to operate using a third bias voltage at the driver stage output, and a final stage transistor electrically coupled to the driver stage output of the peaking-path driver stage transistor is configured to operate using a fourth bias voltage at the final stage output, wherein the third bias voltage is at least twice as large as the first bias voltage.

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 configured to amplify a transmission signal; a first circuit component; and a power amplifier (PA) control circuit configured to control the power amplifier. The power amplifier and the PA control circuit are stacked on the first principal surface, and the first circuit component is disposed on the second principal surface.