A DC-to-DC converter block with multiple supply voltages includes a power circuit, the power circuit including N depletion-mode HEMT transistors (T3_1, T3_2, T3_N), N being a natural number greater than or equal to 3. The DC-to-DC converter block also includes a gate drive circuit for the N depletion-mode HEMT transistors (T3_1, T3_2, T3_N) of the power circuit, the drive circuit including depletion-mode HEMT transistors (T1_1, T2_1, T1_2, T2_2, T1_N, T2_N) configured to drive the gates of the N depletion-mode HEMT transistors (T3_1, T3_2, T3_N) of the power circuit, and the power circuit being powered by N positive and non-zero supply voltages, namely a lower supply voltage (VDD_1), an upper supply voltage (VDD_N), and (N2) intermediate supply voltages (VDD_2) distributed between the lower (VDD_1) and upper (VDD_N) supply voltages.

In a discrete supply modulation system, a circuit includes a multi-stage pulse shaping network (PSN) having a first PSN stage having an input configured to receive variable bias supply signals from a power management circuit (PMC) and having an output coupled to one or more second PSN stages with each of the one or more second PSN stages having an output configured to be coupled to a supply (or bias) terminal of a respective one of one or more radio frequency amplifiers. Such an arrangement is suitable for use with transmit systems in mobile handsets operating in accordance with 5.sup.th generation (5G) communications and other connectivity protocols such as 802.11 a/b/g/n/ac/ax/ad/ay and is suitable for use with multiple simultaneous transmit systems including multiple-input, multiple-output (MIMO), uplink carrier aggregation (ULCA) and beamforming.

An envelope tracking (ET) amplifier apparatus is provided. In examples discussed herein, the ET amplifier apparatus can be configured to operate in a fifth-generation (5G) standalone (SA) mode and a 5G non-standalone (NSA) mode. In the SA mode, the ET amplifier apparatus can enable a first pair of amplifier circuits to amplifier a 5G signal for concurrent transmission in a 5G band(s). In the NSA mode, the ET amplifier apparatus can enable a second pair of amplifier circuits to amplify a non-5G anchor signal and a 5G signal for concurrent transmission in a non-5G anchor band(s) and a 5G band(s), respectively. As such, the ET circuit may be provided in a communication apparatus (e.g., a 5G-enabled smartphone) to help improve power amplifier linearity and efficiency in both 5G SA and NSA modes.

The present application provides a pre-signal amplifier, supply power conditioning apparatus, a wireless communication device and a method for providing selective pre-signal amplifier, supply power conditioning. A selective voltage supply boost stage is included, which has an input coupled to a voltage supply source for receiving a voltage supply, and an output for producing a selectively boosted voltage supply source. A voltage boost circuit is further included having a voltage boost control input coupled to a modem for controlling when the selectively boosted voltage supply source produced at the output is boosted. When the voltage boost control input identifies at least one of one or more modes in which the modem is currently operating, that a boost to the received voltage supply is desired, the resulting selectively boosted voltage supply source produced at the output is boosted.

An envelope tracking (ET) integrated circuit (IC) (ETIC) is provided. The ETIC includes a number of ET circuits coupled to a number of amplifier circuits configured to amplify a radio frequency signal based on a number of ET voltages, respectively. The ET circuits are configured to generate the ET voltages based on a number of ET target voltages, respectively. The ETIC includes a reference ET circuit configured to generate a reference ET voltage based on a maximum ET target voltage among the ET target voltages. A selected ET circuit(s) among the ET circuits may be configured to not generate a respective ET voltage(s) but instead forward the reference ET voltage to a respective amplifier circuit(s) as the respective ET voltage(s). Hence, it may be possible to partially or completely turn off the selected ET circuit(s) to help reduce peak battery current and improve heat dissipation in an ET amplifier apparatus.

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.

The present invention provides a class-G amplifier, wherein the class-G amplifier includes an amplifier stage, an impedance detector and a power source. In the operations of the class-G amplifier, the amplifier stage is supplied by a supply voltage, and amplifies an input audio signal to generate an output audio signal, and the impedance detector is configured to detect an output impedance of the amplifier stage to generate a detection result, and the power source refers to the detection result to determine a level and a switching frequency of the supply voltage.

A supply modulator, a modulated power supply circuit, and associated control method are provided. The modulated power supply circuit includes the supply modulator and a DC-DC voltage converter, and the supply modulator includes a linear amplifier and a switching converter. The linear amplifier generates an AC component of a modulated voltage according to a regulated voltage and an envelope tracking signal. The supply voltage is converted to the regulated voltage by the DC-DC voltage converter, and the regulated voltage is greater than or less than the supply voltage. The switching converter includes a step-down circuit and a path selection circuit. The path selection circuit selects one of the supply voltage and the regulated voltage as a DC input voltage. The step-down circuit converts the DC input voltage to a DC component of the modulated voltage which is less than the DC input voltage.

A multimode power amplifier module, a chip and a communication terminal. In the module, a control circuit (104) sends a bias signal to a low-frequency power amplifier (102) or a high-frequency power amplifier (106) according to a baseband signal, so as to control the amplification of an accessed low-frequency radio frequency signal or a high-frequency radio frequency signal by the low-frequency power amplifier (102) or the high-frequency power amplifier (106); and a transceiving switch (108) selects a corresponding operation mode to conduct transmission or receiving according to an operation mode selection signal. A power amplification path is reused according to different modes, so that the power amplification path can be shared by different operation modes of a high and low frequency band with the adjustment of the control circuit (104), thus simplifying the complexity in designing the power amplifier module, and reducing the cost of relevant design implementation.

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.