Abstract: The present disclosure discloses a direct current (DC)-DC boost converter, which includes a battery terminal providing a battery voltage, a charge pump coupled between the battery terminal and an interior node, and a power inductor coupled between the interior node and a power supply terminal that provides a power voltage to a radio frequency transceiver. The charge pump is configured to provide an interior voltage at the interior node based on the battery voltage. Herein, the interior voltage toggles between the battery voltage and two times the battery voltage. The charge pump includes a first switch coupled between the battery terminal and the interior node, a second switch coupled between the battery terminal and a connecting node, a third switch coupled between the connecting node and ground, and a flying capacitor coupled between the interior node and the connecting node of the second switch and the third switch.

Abstract: A switch controller for charge pump tracker circuitry is disclosed. The switch controller includes first monitoring circuitry configured to monitor a first voltage across a first flying capacitor during a first discharging phase. A second monitoring circuitry is configured to monitor a second voltage across a second flying capacitor during a second discharging phase. Further included is boost logic circuitry in communication with the first monitoring circuitry and the second monitoring circuitry, wherein the boost logic circuitry is configured in response to control a first switch network coupled to the first flying capacitor and a second switch network coupled to the second flying capacitor so that the first discharging phase and the second discharging phase alternate in an interleaved mode, and so that the first discharging phase and the second discharging phase are in phase during a parallel boost mode.

Abstract: An equalizer circuit and related power management circuit are provided. The power management circuit includes a voltage amplifier circuit configured to generate an envelope tracking (ET) voltage based on a differential target voltage and provide the ET voltage to a power amplifier circuit(s) via a signal path for amplifying a radio frequency signal(s). An equalizer circuit is provided in the power management circuit to equalize the differential target voltage prior to generating the ET voltage. Specifically, the equalizer circuit is configured to provide a transfer function including a second-order complex-zero term and a real-zero term for offsetting a transfer function of an inherent trace inductance of the signal path and an inherent impedance of the voltage amplifier circuit. By employing the second-order transfer function with the real-zero term, it is possible to reduce distortion in the ET voltage, especially when the RF signal(s) is modulated in a wide modulation bandwidth.

Abstract: Charge pump tracker circuitry is disclosed having a first switch network configured to couple a first flying capacitor between a voltage input terminal and a ground terminal during a first charging phase and couple the first flying capacitor between the voltage input terminal and a pump output terminal during a first discharging phase. A second switch network is configured to couple a second flying capacitor between the voltage input terminal and the ground terminal during a second charging phase and couple the second flying capacitor between the voltage input terminal and the pump output terminal during a second discharging phase. A switch controller is configured to monitor first and second voltages across the first and second flying capacitors, respectively, during the first and second discharging phases and in response to control the first and second switch networks so that the first the second discharging phases alternate in an interleaved mode.

Abstract: A power management circuit operable to reduce energy loss is provided. The power management circuit is configured to provide a time-variant voltage(s) to a power amplifier(s) for amplifying an analog signal(s). To achieve best possible operating efficiency at the power amplifier(s), the time-variant voltage(s) needs to rise and fall frequently and quickly in accordance with power fluctuations of the analog signal(s). The power management circuit stores an electrical potential energy (e.g., capacitive energy) when the time-variant voltage(s) increases and discharges the electrical potential energy when the time-variant voltage(s) decreases. In embodiments disclosed herein, the power management circuit is configured to harvest a portion of the discharged electrical potential energy to thereby charge a battery. By harvesting the discharged electrical potential energy, it is possible to prolong battery life concurrent to supporting fast and frequent voltage changes.

Abstract: A power management circuit operable with low battery is provided. The power management circuit is configured to generate a time-variant average power tracking (APT) voltage based on a battery voltage supplied by a voltage source (e.g., battery). In examples disclosed herein, the power management circuit can be configured to remain operable when the battery voltage drops below a low battery threshold. Specifically, the power management circuit maintains the time-variant APT voltage at a constant level in response to the battery voltage dropping below the low battery threshold to thereby avoid drawing a rush current from the voltage source. As a result, a wireless device employing the power management circuit can remain operable with low battery to continue to support critical applications.

Abstract: An apparatus that includes a tracking amplifier having an amplifier output terminal coupled to an output voltage node and an envelope input terminal configured to receive an envelope signal of a radio frequency signal is disclosed. A multi-level voltage converter has a switched voltage terminal coupled to the output voltage node and a converter control input terminal configured to receive a converter control signal. A control signal multiplexer has a converter control output terminal coupled to the converter control input terminal, a first converter signal input terminal configured to receive a first converter control signal corresponding to a lower envelope modulation bandwidth, a second converter signal input terminal configured to receive a second converter control signal corresponding to a higher envelope modulation bandwidth, and a converter control signal selector terminal configured to receive a control selector signal for selecting between the first and second converter control signals.

Abstract: A power management circuit operable to reduce rush current is provided. The power management circuit is configured to provide a time-variant voltage(s) to a power amplifier(s) for amplifying a radio frequency (RF) signal(s). Notably, a variation in the time-variant voltage(s) can cause a rush current that is proportionally related to the variation of the time-variant voltage(s). To reduce the rush current, the power management circuit is configured to maintain the time-variant voltage(s) at a non-zero standby voltage level when the power amplifier(s) is inactive. When the power amplifier(s) becomes active and the time-variant voltage(s) needs to be raised or reduced from the non-zero standby voltage level, the rush current will be smaller as a result of reduced variation in the time-variant voltage(s). As such, it is possible to prolong the battery life in a device employing the power management circuit.

Abstract: A power management circuit for fast average power tracking (APT) voltage switching is provided. The power management circuit includes a primary voltage circuit configured to generate an APT voltage based on an APT target voltage. However, the primary voltage circuit may be inherently slow in ramping up the APT voltage to the APT target voltage. As such, a secondary voltage circuit is provided in the power management circuit to help drive the APT voltage to a desired level by a defined temporal limit. Once the APT voltage reaches the desired level, the secondary voltage circuit will automatically shut off, while the primary voltage circuit continues operating at a selected duty cycle to maintain the APT voltage at the APT target voltage. By utilizing the secondary voltage circuit to quickly drive up the APT voltage, the power management circuit is capable of supporting dynamic power control under stringent switching delay budget.

Abstract: An average power tracking (APT) power management circuit is provided. The APT power management circuit is configured to generate a first APT voltage(s) for a first power amplifier(s) and a second APT voltage(s) for a second power amplifier(s). The APT power management circuit further includes a pair of switcher circuits that can generate a pair of reference voltages. Depending on various operating scenarios of the APT power management circuit, it is possible to selectively output any of the reference voltages as any one or more of the first APT voltage(s) and the second APT voltage(s). As such, it is possible to flexibly configure the APT power management circuit to support the various operating scenarios based on a minimum possible number of the switcher circuits, thus helping to reduce footprint and cost of the APT power management circuit.

Abstract: A DC power supply, which includes a DC-DC converter and a linear voltage regulator, is disclosed. The DC-DC converter provides a DC power supply signal and a duty-cycle signal, which is based on a duty-cycle of the DC-DC converter. The DC-DC converter provides the DC power supply signal via a power supply output using a setpoint of the DC power supply. The linear voltage regulator provides a DC assist signal to assist the DC-DC converter when an adjusted setpoint of the DC power supply is greater than a voltage of the DC power supply signal. The linear voltage regulator provides the adjusted setpoint using the setpoint and the duty-cycle signal, such that the adjusted setpoint is directly related to the setpoint and to the duty-cycle.

Abstract: Equalizer circuitry includes a differential target voltage input, an equalizer output, a first operational amplifier, and a second operational amplifier. The differential target voltage input includes a target voltage input node and an inverted target voltage input node. The first operational amplifier and the second operational amplifier are coupled in series between the differential target voltage input and the equalizer output. The first operational amplifier is configured to receive a target voltage signal and provide an intermediate signal based on the target voltage input signal. The second operational amplifier is configured to receive the intermediate signal and an inverted target voltage signal and provide an output signal to the equalizer output.

Abstract: A multimode envelope tracking (ET) circuit and related apparatus is provided. The multimode ET circuit is configured to provide an ET voltage(s) to an amplifier circuit(s) for amplifying a radio frequency (RF) signal(s) that may correspond to a wider range of modulation bandwidth. In this regard, the multimode ET circuit is configured to switch dynamically and opportunistically between different operation modes based on the modulation bandwidth of the RF signal(s). In examples discussed herein, the multimode ET circuit is configured to support a single amplifier circuit in a high-modulation-bandwidth mode and an additional amplifier circuit(s) in a mid-modulation-bandwidth mode and a low-modulation-bandwidth mode.

Abstract: An envelope tracking system is disclosed having an envelope tracking integrated circuit (ETIC) with a first tracker having a first supply output and a second tracker having a second supply output, wherein the ETIC has a first mode in which only one of the first and second trackers supplies voltage and a second mode in which the first and second trackers both supply voltage. A first notch filter is coupled to the first supply output and a second notch filter is coupled to the second supply output. A mode switch coupled between the first supply output and the second supply output is configured to couple the first notch filter and the second notch filter in parallel in the first mode and open the mode switch to decouple the first notch filter from the second notch filter in the second mode in response to first and second switch control signals, respectively.

Abstract: Radio frequency (RF) amplifier circuitry for amplifying an RF input signal to provide an RF output signal includes target envelope supply voltage compensation circuitry, envelope tracking power supply circuitry, and power amplifier circuitry. The target envelope supply voltage compensation circuitry is configured to compensate a target envelope supply voltage to provide a compensated target envelope supply voltage, which is used by the envelope tracking power supply circuitry to provide an output envelope supply voltage. The power amplifier circuitry is configured to amplify the RF input signal using a power amplifier envelope supply voltage. The power amplifier envelope supply voltage is different from the output envelope supply voltage due to a parasitic impedance. The target envelope supply voltage compensation circuitry is configured to compensate the target envelope supply voltage to reduce an error between the target envelope supply voltage and the power amplifier envelope supply voltage.

Abstract: A multi-level charge pump (MCP) circuit is provided. The MCP circuit includes a multi-level voltage circuit configured to receive a supply voltage and generate a low-frequency voltage. The multi-level voltage circuit includes a first switch path, a second switch path, and a third switch path each having a respective on-resistance and coupled in parallel between an input node and an output node. In a non-limiting example, the multi-level voltage circuit is configured to activate the first switch path and at least one of the second switch path and the third switch path when the multi-level voltage circuit generates the low-frequency voltage that equals the supply voltage. By activating at least two of the three switch paths to generate the low-frequency voltage, it may be possible to reduce an equivalent resistance of the multi-level voltage circuit, thus helping to improve efficiency and reduce power loss of the MCP circuit.

Abstract: A voltage generation circuit and related envelope tracking (ET) amplifier apparatus is provided. In examples discussed herein, a voltage generation circuit can be provided in an ET amplifier apparatus to provide a supply voltage to a voltage amplifier(s) that is configured to generate an ET voltage for an amplifier circuit(s). In a non-limiting example, the voltage amplifier(s) receives an ET target voltage signal corresponding to a time-variant target voltage envelope and generates the ET voltage conforming to the time-variant target voltage envelope. The voltage generation circuit is configured to generate one or more supply voltages and selectively provide one of the supply voltages to the voltage amplifier(s) in accordance to the time-variant target voltage envelope. By selectively providing the supply voltage based on the time-variant target voltage envelope, it may be possible to improve efficiency of the voltage amplifier, thus helping to improve efficiency and linearity of the amplifier circuit(s).

Abstract: Charge pump tracker circuitry is disclosed having a first switch network configured to couple a first flying capacitor between a voltage input terminal and a ground terminal during a first charging phase and couple the first flying capacitor between the voltage input terminal and a pump output terminal during a first discharging phase. A second switch network is configured to couple a second flying capacitor between the voltage input terminal and the ground terminal during a second charging phase and couple the second flying capacitor between the voltage input terminal and the pump output terminal during a second discharging phase. A switch controller is configured to monitor first and second voltages across the first and second flying capacitors, respectively, during the first and second discharging phases and in response to control the first and second switch networks so that the first the second discharging phases alternate in an interleaved mode.

Abstract: Charge-pump tracker circuitry is disclosed having a first switch network configured to couple a first capacitor between a voltage input terminal and a ground terminal during a first charging phase and couple the first capacitor between the voltage input terminal and a pump output terminal during a first discharging phase. A second switch network is configured to couple the second capacitor between the voltage input terminal and the ground terminal during a second charging phase and couple the second capacitor between the voltage input terminal and the pump output terminal during a second discharging phase. A switch controller is configured to control the first switch network and the second switch network so that the first discharging phase and the second discharging phase are in unison in a parallel mode and so that the first discharging phase and the second discharging phase alternate in an interleaved mode.

Abstract: A power switch with a bootstrap driver for continuous time operation is disclosed. In an exemplary aspect, the power switch selectively connects power management circuitry to one or more power amplifier stages in a radio frequency (RF) front end. The bootstrap driver provides a constant gate to source voltage during an enabled state of the power switch such that a switching element can remain closed with near-constant closed switch resistance in the presence of varying signals (e.g., varying power signals) passing through the power switch. The bootstrap driver can use a variable clock frequency to quickly close the power switch and resistor-capacitor (RC) filtering to reduce noise contribution to the signal path through the power switch. In some examples, a constant voltage reference provides battery independent voltage control of the gate to source voltage of the power switch.