Disclosed is envelope tracking circuitry having an envelope tracking integrated circuit (ETIC) coupled to a power supply to provide an envelope tracked power signal to a power amplifier (PA) with a filter equalizer configured to inject an error-correcting signal into the ETIC in response to equalizer settings. Further included is PA resistance estimator circuitry having a first peak detector circuit configured to capture within a window first peaks associated with a sense current generated by the ETIC, a second peak detector circuit configured to capture within the window second peaks associated with a scaled supply voltage corresponding to the envelope tracked power signal, comparator circuitry configured to receive the first peaks and receive the second peaks and generate an estimation of PA resistance, and an equalizer settings correction circuit configured to receive the estimation of PA resistance and update the equalizer settings in response to the estimation of PA resistance.

A power supply switch circuit includes a first transistor that switches supplying of a first power supply voltage to a power supply terminal of a power amplifier, a switch controller that controls the first transistor and to which a second power supply voltage is applied, and a voltage selector that selects a higher voltage among the first power supply voltage and the second power supply voltage. The selected higher voltage is applied to a body terminal of the first transistor or a gate terminal of the first transistor.

An envelope tracking (ET) integrated circuit (ETIC) supporting multiple types of power amplifiers. The ETIC includes a pair of tracker circuits configured to generate a pair of low-frequency currents at a pair of output nodes, respectively. The ETIC also includes a pair of ET voltage circuits configured to generate a pair of ET voltages at the output nodes, respectively. In various embodiments disclosed herein, the ETIC can be configured to generate the low-frequency currents independent of what type of power amplifier is coupled to the output nodes. Concurrently, the ETIC can also generate the ET voltages in accordance with the type of power amplifier coupled to the output nodes. As such, it is possible to support multiple types of power amplifiers based on a single ETIC, thus helping to reduce footprint, power consumption, and heat dissipation in an electronic device employing the ETIC and the multiple types of power amplifiers.

Systems, methods and apparatus for practical realization of an integrated circuit comprising a stack of transistors operating as an RF amplifier are described. As stack height is increased, capacitance values of gate capacitors used to provide a desired distribution of an RF voltage at the output of the amplifier across the stack may decrease to values approaching parasitic/stray capacitance values present in the integrated circuit which may render the practical realization of the integrated circuit difficult. Coupling of an RF gate voltage at the gate of one transistor of the stack to a gate of a different transistor of the stack can allow for an increase in the capacitance value of the gate capacitor of the different transistor for obtaining an RF voltage at the gate of the different transistor according to the desired distribution.

A power supply modulator circuit includes a multi-output power supply that generates multiple power output signals; at least one power modulator circuit generates a modulated power output signal from the multiple power output signals of the multi-output power supply; at least one pulse shaping network (PSN) having at least one passive element, the PSN configured to shape the modulated power output signal; at least one power amplifier coupled to receive the modulated power signal; and a switching network having a plurality of switches to create or modify power signal paths from the at least one power modulator circuit to the at least one power amplifier.

A power supply switch circuit includes a first switch configured to supply a first power supply voltage to a power supply terminal of a power amplifier, a control voltage generator configured to compare a first voltage of the power supply terminal with a predetermined first reference voltage to generate a first control voltage higher than the first power supply voltage, and a switch controller configured to use the first control voltage to generate a switching driving signal controlling the first switch.

A power supply switch circuit includes: a first switch to switch supply of a first power supply voltage to a power supply terminal of a power amplifier; a control voltage generator to generate a first control voltage through a charge pump operation, and to control the charge pump operation by comparing the first power supply voltage to a first voltage, which is a voltage of the power supply terminal; and a switch controller to generate a switching driving signal to control the first switch using the first control voltage.

Various implementations include a common mode voltage controller for a self-boosting push pull amplifier. In some implementations, input signal are processed by: calculating, based upon the input signal, a maximum duty cycle to achieve a target differential in an output of the self-boosting push pull amplifier; calculating, based on the input signal, a set of control parameters associated with adjusting a common mode voltage of the output; and generating, based on the input signal, a pair of signals configured to adjust the common mode voltage of the output, wherein the pair of signals include a gain adjustment and offset based on the maximum duty cycle and the set of control parameters, and wherein the pair of signals are configured to maintain the target differential in the output of the self-boosting push pull amplifier as the common mode voltage is adjusted to a different operating point.

The invention discloses a transmitter comprising a pulse encoder for creating pulses from the amplitude of an input signal to the transmitter, a compensation signal generator for cancelling quantization noise caused by the pulse encoder, a mixer or I/Q modulator for mixing an output of the pulse encoder with the phase of an input signal to the transmitter, said output of the pulse encoder comprising the amplitude of the complex input signal plus the quantization noise caused by the pulse encoder, and an amplifier for creating an output signal from the transmitter. In the transmitter, a control signal (C.sub.A) for controlling a function of the amplifier comprises an output signal from the compensation signal generator, and an input signal to the amplifier comprises an output from the mixer having been modulated to a desired frequency.

A switching system is connected to the power amplifier of an RF system. The switching system can switch the DC supply voltage to the power amplifier while handling the high DC current and the nanosecond switching speed requirements that are mandatory for most RF systems. The embodiments can rapidly control DC voltages but not interfere with the optimized operation of the RF transistor. The embodiments provide a desired sharp turn-on leading edge for an RF pulse while eliminating the extremely long and undesirable ramp down that typically occurs beyond the desired RF pulse period.