A radio frequency (RF) equalizer in an envelope tracking (ET) circuit is disclosed. A transmitter chain includes an ET circuit having an RF equalizer therein. The RF equalizer includes a two operational amplifier (op-amp) structure that provides a relatively flat gain and a relatively constant negative group delay across a frequency range of interest (e.g., up to 200 MHz). The simple two op-amp structure provides frequency response equalization and time tuning adjustment and/or creates a window Vcc signal.

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.

The wireless RF semiconductor system is described for use in wireless communication devices that operate in frequency range from approximately 6 GigaHertz (GHz) to 100 GHz. The system comprises of at least one RF antenna and at least one RF integrated circuit fabricated (or built) on the same semiconductor substrate inside a one single packaged module. The wireless RF semiconductor system is described in a variety of different configurations with its functionality divided up over several single chip circuits. The system simplifies assembly, reduces size and cost, and allows for a quick time to market, while maximizing the RF performance demanded by fixed and mobile 4G, 5G and other wireless standards. The system uses a novel idea of configuration and packaging of active and passive RF components into a single module. This in turn allows RF manufacturers to unlock the potential of very high frequencies operation that were previously thought too expensive and unattainable to average user. The wireless RF semiconductor system can be implemented in both mobile solutions (such as phones and tablets) and fixed applications (such as repeaters, base-stations, and distributed antenna systems).

A near-field transmitter includes a power amplifier, a resonant network, an envelope detector, and an antenna tuning circuit. The power amplifier has an input for receiving a communication signal, and an output for providing a differential output signal. The resonant network is coupled to the output of the power amplifier and has a tunable reactive element tuned by a tuning signal. The envelope detector is coupled to the output of the power amplifier for providing an envelope signal in response to the differential output signal. The antenna tuning circuit is for adjusting the tuning signal in response to the envelope signal.

A radio frequency amplifying device according to an embodiment includes load impedance calculating circuitry and controlling circuitry. The load impedance calculating circuitry is configured to calculate a load impedance on the basis of information about a voltage standing wave rate and a phase on an output side of radio frequency amplifying circuitry. The controlling circuitry is configured to adjust a gain and a phase of a signal to be input to the radio frequency amplifying circuitry, in accordance with the load impedance calculated by the load impedance calculating circuitry.

An envelope tracking method and device are provided. The envelope tracking method includes: acquiring, by a boost circuit, a target envelope tracking input current signal, and transmitting, by the boost circuit, the target envelope tracking input current signal to an amplifier circuit, where the amplifier circuit includes an operational amplifier and a feedback network, and the operational amplifier operates in a mode of floating ground; and performing, by the amplifier circuit, closed-loop conversion and amplification on the target envelope tracking input current signal and outputting, by the amplifier circuit, an envelope tracking output voltage.

An amplifier overload power limit circuit, system, and a method thereof comprising a monitoring of a current gain of a BJT based on a current detector and limiting power to the BJT based on the monitored current gain to prevent the BJT from driven into a saturation mode and the amplifier overdrive.

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.

A radio-frequency circuit is provided that includes a power amplifier, a control circuit, an on-off switch, a connection terminal, and a mount board. The power amplifier supports an APT system and an ET system. The control circuit controls the power amplifier by using the APT system and the ET system. The on-off switch is connected in series to a capacitive element connected between a path and the ground. The connection terminal is connected to the capacitive element. Moreover, the control circuit overlies the connection terminal in plan view in the thickness direction of the mount board.

A semiconductor device is provided in which power consumption is reduced and an increase in circuit area is inhibited. The semiconductor device includes a high frequency amplifier circuit, an envelope detection circuit, and a power supply circuit. The power supply circuit has a function of supplying a power supply potential to the high frequency amplifier circuit, an output of the high frequency amplifier circuit is connected to the envelope detection circuit, and an output of the envelope detection circuit is connected to the power supply circuit. The power supply circuit can reduce the power consumption by changing the power supply potential in accordance with the output of the high frequency amplifier circuit. The use of an OS transistor in the envelope detection circuit can inhibit an increase in circuit area.