A class-D amplifier including a pulse width modulator including an input configured to receive a first signal based on an input signal, and an output configured to generate a pulse width modulated (PWM) signal; an H-bridge including an input coupled to an output of the pulse width modulator and an output coupled to a load, wherein the H-bridge is configured to generate an output signal across the load based on the PWM signal; and a deadtime compensation circuit coupled to the H-bridge, wherein the deadtime compensation circuit is configured to compensate for deadtime distortion in the output signal. The deadtime compensation circuit may be a feedback circuit between an output of the H-bridge and an input of the pulse width modulator, a pulse modification circuit at the output of the pulse width modulator, or an offset signal generating circuit providing an offset signal to the pulse width modulator.

An embodiment apparatus comprises a switching-type output power stage, a modulator circuit configured for carrying out a pulse-width modulation and converting an electrical input signal into an input signal pulsed between two electrical levels, having a mean value proportional to the amplitude of the input signal, and a circuit arrangement for controlling saturation of an output signal supplied by the switching-type output power stage. The circuit arrangement comprises a pulse-remodulator circuit, between the output of the modulator circuit and the input of the switching-type output power stage, that is configured for supplying, as a driving signal to the switching-type output power stage, a respective modulated signal pulsed between two electrical levels, measuring a pulse width as pulse time interval elapsing between two consecutive pulsed-signal edges of the pulsed input signal, and, if the measurement indicates that the latter is below a given minimum value, remodulating the pulsed input signal.

An embodiment apparatus comprises a switching-type output power stage, a modulator circuit configured for carrying out a pulse-width modulation and converting an electrical input signal into an input signal pulsed between two electrical levels, having a mean value proportional to the amplitude of the input signal, and a circuit arrangement for controlling saturation of an output signal supplied by the switching-type output power stage. The circuit arrangement comprises a pulse-remodulator circuit, between the output of the modulator circuit and the input of the switching-type output power stage, that is configured for supplying, as a driving signal to the switching-type output power stage, a respective modulated signal pulsed between two electrical levels, measuring a pulse width as pulse time interval elapsing between two consecutive pulsed-signal edges of the pulsed input signal, and, if the measurement indicates that the latter is below a given minimum value, remodulating the pulsed input signal.

A semiconductor IC includes a first radio-frequency element (e.g., an inductor in a low-noise amplifier), a second radio-frequency element (e.g., an inductor in a low-noise amplifier), a first via conductor (e.g., a via conductor that is placed between the first radio-frequency element and the second radio-frequency element and that is connected to a ground potential.

A transmitter/receiver apparatus including: a transmitter/receiver terminal; a switching amplifier that includes a low-side switching element connected between a ground terminal and a pulse output terminal and a high-side switching element connected between the pulse output terminal and a power supply terminal and that outputs a pulse signal from the pulse output terminal; a filter that passes therethrough and outputs as a transmitted signal a predetermined frequency component of the pulse signal from a transmitter terminal; and a transmit/receive switch unit that switches the connection status between the transmitter/receiver terminal and the transmitter terminal and also switches the connection status between the transmitter/receiver terminal and a receiver terminal. During receiving, on the basis of the connection status between the transmitter/receiver terminal and the transmitter terminal, the low-side and high-side switching elements are fixed to conductive and non-conductive states, respectively, to non-conductive and conductive states, respectively, or both to non-conductive states.

A transmitter/receiver apparatus including: a transmitter/receiver terminal; a switching amplifier that includes a low-side switching element connected between a ground terminal and a pulse output terminal and a high-side switching element connected between the pulse output terminal and a power supply terminal and that outputs a pulse signal from the pulse output terminal; a filter that passes therethrough and outputs as a transmitted signal a predetermined frequency component of the pulse signal from a transmitter terminal; and a transmit/receive switch unit that switches the connection status between the transmitter/receiver terminal and the transmitter terminal and also switches the connection status between the transmitter/receiver terminal and a receiver terminal. During receiving, on the basis of the connection status between the transmitter/receiver terminal and the transmitter terminal, the low-side and high-side switching elements are fixed to conductive and non-conductive states, respectively, to non-conductive and conductive states, respectively, or both to non-conductive states.

A frequency dependent dynamic range control method is employed in a signal emitting system characterized by lower impedance in the high frequency region. An efficient technique is implemented to dynamically estimate current spectrum and conditioning parameters to lower the current in the high frequency region. The method advantageously avoids current overloading without using a series resistor as a current limiter.

A method can be used to measure a load driven by a switching amplifier having a differential input, an LC output demodulator filter and a feedback network between the amplifier output and the differential input. The amplifier is AC driven in a differential and in a common mode by applying a common. The feedback network provides feedback towards the differential input from downstream the LC demodulator filter by computing the impedance of the load as a function of the differential mode output current and the common mode output current. The feedback network provides feedback towards the differential input from upstream the LC demodulator filter by measuring the impedance value of the inductor of the LC demodulator filter, and computing the impedance of the load as a function of the differential mode output current, the common mode output current and the impedance value of the inductor of the LC demodulator filter.

A method can be used to measure a load driven by a switching amplifier having a differential input, an LC output demodulator filter and a feedback network between the amplifier output and the differential input. The amplifier is AC driven in a differential and in a common mode by applying a common. The feedback network provides feedback towards the differential input from downstream the LC demodulator filter by computing the impedance of the load as a function of the differential mode output current and the common mode output current. The feedback network provides feedback towards the differential input from upstream the LC demodulator filter by measuring the impedance value of the inductor of the LC demodulator filter, and computing the impedance of the load as a function of the differential mode output current, the common mode output current and the impedance value of the inductor of the LC demodulator filter.

An eVC including coarse and fine tuning networks. The coarse tuning network includes a circuit: receiving a RF input signal from a RF generator; outputting a RF output signal to a reference terminal or load; and receiving a DC bias voltage. The circuit is switched between first and second states. A capacitance of the circuit is based on the DC bias voltage while in the first state and is not based on the DC bias voltage while in the second state. The fine tuning network is connected in parallel with the coarse tuning network and includes a varactor. The varactor includes: a first diode receiving the RF input signal; and a second diode connected in a back-to-back configuration with the first diode and outputting a RF output signal to the reference terminal or load. A capacitance of the varactor is based on a second received DC bias voltage.