Charging and discharging circuits for assisting charge pumps are disclosed. In certain embodiments, a radio frequency (RF) switch system includes an RF switch that receives an RF signal and is controlled by a switch control signal received at an input, a first charge pump configured to generate a first charge pump voltage, a level shifter powered by the first charge pump voltage and that generates the switch control signal based on a switch enable signal, and a charge pump assistance switch coupled to the input of the radio frequency switch and that activates to assist the first charge pump in response to a transition of the switch enable signal from a first state to a second state.

Charging and discharging circuits for assisting charge pumps are disclosed. In certain embodiments, a radio frequency (RF) switch system includes an RF switch that receives an RF signal and is controlled by a switch control signal received at an input, a first charge pump configured to generate a first charge pump voltage, a level shifter powered by the first charge pump voltage and that generates the switch control signal based on a switch enable signal, and a charge pump assistance switch coupled to the input of the radio frequency switch and that activates to assist the first charge pump in response to a transition of the switch enable signal from a first state to a second state.

A fully differential power amplifier has an input matching network, a plurality of stacked transistors connected by a plurality of inter stack networks (ISNs), and an output matching network for amplification and conditioning of signal components. The differential amplifier uses a modified cascode FET topology with the FETs connected by gate decoupling capacitors to strongly attenuate common mode oscillations and eliminate the need for a source degeneration inductor or matching transformer. Inter stack networks provide signal conditioning and filtering between amplification stages to improve amplifier performance metrics such as long-term reliability, output power, and efficiency.

A fully differential power amplifier has an input matching network, a plurality of stacked transistors connected by a plurality of inter stack networks (ISNs), and an output matching network for amplification and conditioning of signal components. The differential amplifier uses a modified cascode FET topology with the FETs connected by gate decoupling capacitors to strongly attenuate common mode oscillations and eliminate the need for a source degeneration inductor or matching transformer. Inter stack networks provide signal conditioning and filtering between amplification stages to improve amplifier performance metrics such as long-term reliability, output power, and efficiency.

There is provided a quasi-circulator. The quasi-circulator includes: a first coupler having an input end connected to a transmission end; a first amplifier having an input end connected to an output end of the first coupler; a second amplifier having an input end connected to the output end of the first coupler; a second coupler having one end connected to an output end of the first amplifier and an output end of the second amplifier, and the other end connected to an antenna; and a third coupler having one end connected to the output end of the first amplifier and the output end of the second amplifier, and the other end connected to a reception end. Accordingly, a loss occurring at the quasi-circulator is minimized, and eventually, efficiency of an RF FEM employed in an ultrahigh frequency radar system is enhanced.

One or more aspects of the techniques and models described herein provide for bidirectional recurrent neural network (BiRNN)-based digital pre-distortion techniques for radio frequency (RF) power amplifiers (PAs). As an example, a digital pre-distorter (DPD) system may implement residual learning and long short-term memory (LSTM) projection layer features to reduce computational complexity and memory requirements. Implementing the described unconventional techniques of applying residual learning in RNN (e.g., in BiLSTM), using LSTM projection to develop a DPD structure, or both, may provide several advantages over preexisting techniques. For instance, the complexity in training and pre-distortion may be reduced and significantly less memory may be required to store the DPD neural network coefficients (e.g., while achieving similar or better linearization performance compared to other LSTM models). Further, faster training convergence speed may be achieved (e.g., compared to other LSTM models).

A clamp circuit comprises a first diode stack comprising one or more diodes and an array comprising a second diode stack comprising one or more diodes and a comparator configured to compare a first voltage at the first diode stack to a second voltage at the second diode stack.

An acoustic wave device includes a piezoelectric substrate including a support substrate and a piezoelectric layer on the support substrate, the piezoelectric substrate including a first principal surface on the piezoelectric layer side, and a second principal surface on the support substrate side, an IDT electrode on the first principal surface, a support layer on the support substrate, a cover on the support layer, a through-via electrode provided through the support substrate and electrically connected to the IDT electrode, a first wiring electrode on the second principal surface of the piezoelectric substrate and electrically connected to the through-via electrode, and a protective film on the second principal surface to cover at least a portion of the first wiring electrode. The protective film is provided on an inner side of the support layer when viewed in a direction normal or substantially normal to the second principal surface.

An electronic device and method thereof of are provided to prevent burnout due to overcurrent. An electronic device includes a power amplifier configured to amplify a transmission signal; a battery configured to provide a bias voltage to the at least one power amplifier; and an overcurrent protection circuit configured to prevent overcurrent from flowing through the power amplifier. The overcurrent protection circuit includes a configurer configured to configure a reference current value, based on the power amplifier; a measurer configured to measure a bias current value due to the bias voltage; a comparator configured to compare the measured bias current value with the reference current value; and a controller configured to recognize overcurrent flowing through the power amplifier and control provision of the bias voltage, based on a result of the comparison.

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.