Envelope tracking for radio frequency (RF) front-end modules

Abstract

Aspects described herein include apparatuses and methods for generating a supply voltage for a power amplifier. One aspect is an apparatus including a first amplifier and a second amplifier having a control input, wherein the control input of the second amplifier is configured to set a power state for the second amplifier. The apparatus has an input interface circuit coupled to the two amplifiers, a sensing and conditioning circuit coupled between the amplifier outputs and a switching circuit, and an output filter circuit via which the output of the first amplifier is coupled to an output power port, and wherein the output of the second amplifier is coupled to the output power port via the output filter circuit.

Description

Technical Field

[0001] The present disclosure relates generally to electronics and wireless communications. For example, aspects of the present disclosure relate to power envelope tracking and power management in a radio frequency (RF) front end (RFFE) module used in wireless communications. Background Art

[0002] Wireless communication devices and technologies are becoming more and more common. Wireless communication devices typically transmit and receive communication signals. RFFE modules are wireless communication devices that power wireless transmission signals and may also manage the reception of wireless signals from antennas. With the increasing popularity of wireless communication technologies and the increased communication system throughput and the increased complexity of power management for wireless devices, RFFE modules are becoming larger components of wireless devices. Limiting power usage and managing power efficiency are important goals of device design, especially for mobile devices. Summary of the invention

[0003] Various implementations of systems, methods, and devices within the scope of the appended claims each have several aspects, no single one of which is solely responsible for the desirable attributes described herein. Without limiting the scope of the appended claims, certain governing features are described herein.

[0004] Various aspects described herein include devices, wireless communication apparatus, circuits, and modules supporting wireless communications in which an envelope tracking power source is used to match the power provided to a transmit power amplifier to the power required by a signal to be transmitted via an antenna.

[0005] One aspect is a method for amplifying a wireless communication signal. The method includes calculating envelope information for a transmit signal by a control circuit of a modem; generating the transmit signal by a radio frequency front end (RFFE); providing a voltage to a power amplifier of the RFFE through an envelope tracking power source, wherein the envelope tracking power source includes: an envelope signal input port, the envelope signal input port is configured to receive an envelope tracking signal generated according to the envelope information; an output power port, the output power port is configured to provide the voltage to the power amplifier; a first amplifier, the first amplifier having an input and an output; a second amplifier, the second amplifier having an input, an output and a control input, wherein the control input of the second amplifier is configured to program the second amplifier based on a current operating mode selected from a plurality of operating modes; an input interface circuit, The input interface circuit has an input coupled to the envelope signal input port, a first output coupled to the input of the first amplifier, and a second output coupled to the input of the second amplifier; a sensing and conditioning circuit having an output and one or more inputs coupled to the output of the first amplifier and the output of the second amplifier; a switching circuit having an input and an output, wherein the input is coupled to the output of the sensing and conditioning circuit, and wherein the output is coupled to the output power port; and an output filter circuit, wherein the output of the first amplifier is coupled to the output power port via the output filter circuit, and wherein the output of the second amplifier is coupled to the output power port via the output filter circuit.

[0006] In some aspects, such methods operate where providing a voltage to a power amplifier includes programming a second amplifier with a control input signal at a control input, wherein the control input signal is based on a current operating mode, a radio access technology (RAT) configuration, a peak-to-average power ratio of a radio frequency (RF) signal, or a bandwidth of the RF signal.

[0007] Another aspect is a wireless communication device, which includes: a component for calculating envelope information for a transmission signal; a component for generating the transmission signal; and a component for providing an envelope tracking voltage to power a power amplifier that amplifies the transmission signal.

[0008] Another aspect is a device. The device is an envelope tracking power source, the envelope tracking power source comprising: an envelope signal input port; an output power port; a first amplifier, the first amplifier having an input and an output; a second amplifier, the second amplifier having an input, an output, and a control input, wherein the control input of the second amplifier is configured to set a power state for the second amplifier; an input interface circuit, the input interface circuit having an input coupled to the envelope signal input port, a first output coupled to the input of the first amplifier, and a second output coupled to the input of the second amplifier; a sensing and conditioning circuit having an output and one or more inputs coupled to the output of the first amplifier and the output of the second amplifier; a switching circuit having an input and an output, wherein the input is coupled to the output of the sensing and conditioning circuit, and wherein the output is coupled to the output power port; and an output filter circuit, wherein the output of the first amplifier is coupled to the output power port via the output filter circuit, and wherein the output of the second amplifier is coupled to the output power port via the output filter circuit.

[0009] Some such aspects operate with the first amplifier being a main amplifier configured to provide linear amplification. Some such aspects operate with a control input configuring a power state for the second amplifier by switching the second amplifier between an on state and an off state. Some such aspects operate with the second amplifier being a peaking amplifier.

[0010] Some such aspects operate with the second amplifier configured to operate in a saturation mode during the on state. Some such aspects operate with the control input configuring the power state based on a current operating mode selected from a plurality of operating modes. Some such aspects operate with the plurality of operating modes including a high power mode and a low power mode. Some such aspects operate at the control input further based on one or more of a radio access technology (RAT) configuration, a peak-to-average power ratio of a radio frequency (RF) signal, and a bandwidth of the RF signal.

[0011] Some such aspects also include a feedback circuit coupled between the sensing and conditioning circuit and the control input of the second amplifier, wherein the feedback circuit provides a feedback signal from the sensing and conditioning circuit to the control input to adjust a match between a power demand of a power amplifier coupled to the output power port and a voltage provided by the switching circuit, the first amplifier, and the second amplifier at the output power port.

[0012] Some such aspects also include a first sensing element coupled between an output of the first amplifier and an input of the sensing and conditioning circuit; and a second sensing element coupled between an output of the second amplifier and a second input of the sensing and conditioning circuit.

[0013] Some such aspects also include a sensing element having an input and an output, wherein the input is coupled to an output of the first amplifier and an output of the second amplifier, and wherein the output is coupled to an input of the sensing and conditioning circuit.

[0014] Some such aspects further operate where the output filter circuit includes a first filter circuit coupled between the output of the first amplifier and the output power port; wherein the output filter circuit also includes a second filter circuit different from the first filter circuit, wherein the second filter circuit is coupled between the output of the second amplifier and the output power port.

[0015] Some such aspects further operate where the first amplifier is a class AB amplifier and where the second amplifier is a class C amplifier, where the first amplifier is a linear amplifier, or where the second amplifier is a switching amplifier.

[0016] Some such aspects further operate where the input interface circuit is configured to receive a digital envelope signal at an envelope signal input port; wherein the input interface circuit is configured to output a first tracking signal at a first output terminal based on a set of least significant bits of the digital envelope signal; and wherein the input interface circuit is configured to output a second tracking signal based on one or more most significant bits of the digital envelope signal.

[0017] In some aspects, the apparatus described above may function in a system including a mobile device having a camera for capturing one or more pictures. In some aspects, the apparatus described above may include a display screen for displaying one or more images or interface displays. In some aspects, additional wireless communication circuits are provided. This summary is not intended to identify the key or essential features of the claimed subject matter, nor is it intended to be used independently to determine the scope of the claimed subject matter. This subject matter should be understood with reference to appropriate portions of the entire specification, any or all drawings, and each claim.

[0018] The foregoing and other features and embodiments will become more apparent upon reference to the following description, claims and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In the drawings, like reference numerals refer to like parts throughout the various views unless otherwise indicated. For reference numerals with alphabetic characters, such as "102a" or "102b", the alphabetic characters may distinguish between two similar parts or elements in the same figure. When it is intended that a reference numeral encompass all parts having the same reference numeral in all figures, the alphabetic characters of the reference numeral may be omitted.

[0020] Figure 1 is a diagram illustrating a wireless communication system for communicating with wireless devices that can be implemented in accordance with various aspects described herein.

[0021] Figure 2 is a block diagram illustrating portions of a wireless device in which aspects of the present disclosure may be implemented.

[0022] Figure 3A is a chart illustrating power envelope tracking for an RFFE module in accordance with various aspects described herein.

[0023] Figure 3B is a high-level block diagram of a system for power envelope tracking for an RFFE module in accordance with the various aspects described herein.

[0024] Figure 4 is a block diagram illustrating aspects of a system for controlling power provided to an RFFE power amplifier using power envelope tracking according to the aspects described herein.

[0025] Figure 5 is a block diagram illustrating aspects of a system for controlling power provided to an RFFE power amplifier using power envelope tracking according to the aspects described herein.

[0026] Figure 6 is a block diagram illustrating aspects of a system for controlling power provided to an RFFE power amplifier using power envelope tracking according to the aspects described herein.

[0027] Figure 7 is a block diagram illustrating aspects of a system for controlling power provided to an RFFE power amplifier using power envelope tracking according to the aspects described herein.

[0028] Figure 8 is a block diagram illustrating aspects of a system for controlling power provided to an RFFE power amplifier using power envelope tracking according to the aspects described herein.

[0029] Fig. 9 is a flow chart illustrating a method according to aspects of the present disclosure.

[0030] Fig.10is a functional block diagram of an apparatus including power envelope tracking to control power provided to an RFFE power amplifier according to some aspects of the present disclosure.

[0031] Fig.11 is a diagram illustrating an environment including electronic devices and base stations that may be used with aspects of the present disclosure.

[0032] Fig.12 is a diagram of an electronic device that may be used with aspects of the present disclosure. DETAILED DESCRIPTION

[0033] The specific embodiments described below in conjunction with the drawings are intended as descriptions of example aspects and specific implementations and are not intended to represent the only specific implementations in which the present invention may be practiced. The specific embodiments include specific details for the purpose of providing a thorough understanding of the example aspects and specific implementations. In some instances, some devices are shown in block diagram form. Common drawing elements in the following figures may be identified using the same reference numerals.

[0034] The development of wireless communication infrastructure, such as for the 3rd Generation Partnership Project (3GPP) fifth generation (5G) millimeter wavelength (mmW) systems, involves increasing importance of radio frequency (RF) front end (RFFE) modules. For example, the 5G standard for cellular communications involves increasing complexity of frequency combinations and communication throughput options. The power amplifiers that implement RFFE operations consume significant amounts of power in environments where power dissipation and power efficiency are important operating characteristics, especially for portable systems.

[0035] Various aspects described herein include improved envelope tracking systems for wireless transmit communications that are used to match the voltage headroom or voltage available to a transmit power amplifier in an RFFE with the required power identified by envelope tracking. Various aspects described herein further improve the operation of the RFFE module by using multiple amplifiers in the envelope tracking and power supply system that supports the power amplifiers in the RFFE transmit chain. In particular, by using multiple envelope tracking system amplifiers that support different operating conditions, power efficiency is increased and unnecessary power dissipation is reduced, and over-provisioning of power to the transmit power amplifier corresponding to excessive power dissipation and associated heat dissipation is limited.

[0036] Further details regarding various aspects described herein are provided with respect to the following figures.

[0037] Figure 11 is a diagram showing a wireless device 110 communicating with a wireless communication system 120. According to various aspects described herein, a wireless device may include an electronic device having wireless communication capabilities enabled by an RFFE module along with other wireless communication elements. Devices within the system 120 may use envelope power tracking and power amplifier support to improve power efficiency of devices such as wireless communication devices operating in the communication system 120.

[0038] The wireless communication system 120 may be a Long Term Evolution (LTE) system, a Code Division Multiple Access (CDMA) system, a Global System for Mobile Communications (GSM) system, a Wireless Local Area Network (WLAN) system, a 5G NR (New Radio) system, or some other wireless system. The CDMA system may implement Wideband CDMA (WCDMA), CDMA 1X, Evolution Data Optimized (EVDO), Time Division Synchronous CDMA (TD-SCDMA), or some other version of CDMA. The communication elements of the wireless device 110 for implementing mmW communications and non-mmW communications according to any such communication standards may be supported by various designs of transceivers using chained signal routing. For simplicity, Figure 1 A wireless communication system 120 is shown including two base stations 130 and 132 and one system controller 140. In general, a wireless communication system may include any number of base stations and any set of network entities.

[0039] The wireless device 110 may also be referred to as a user equipment (UE), a mobile station, a terminal, an access terminal, a subscriber unit, a station, etc. The wireless device 110 may be a cellular phone, a smart phone, a tablet computer, or other such mobile device (e.g., a device integrated with a display screen). Other examples of the wireless device 110 include a wireless modem, a personal digital assistant (PDA), a handheld device, a laptop computer, a smart book, a netbook, a tablet computer, a cordless phone, a medical device, a device configured to be connected to one or more other devices (e.g., via the Internet of Things), a wireless local loop (WLL) station, a Bluetooth device, etc. The wireless device 110 may communicate with the wireless communication system 120. The wireless device 110 may also receive signals from a broadcast station (e.g., a broadcast station 134) and / or signals from a satellite (e.g., a satellite 150 in one or more global navigation satellite systems (GNSS)). The wireless device 110 may support one or more radio technologies for wireless communication, such as LTE, WCDMA, CDMA1X, EVDO, TD-SCDMA, GSM, 802.11, 5G, etc.

[0040] The wireless communication system 120 may also include a wireless device 160. In an exemplary embodiment, the wireless device 160 may be a wireless access point, or another wireless communication device that includes or includes a portion of a wireless local area network (WLAN). In an exemplary embodiment, the wireless device 110 may be configured as a customer premises equipment (CPE) that can communicate with the base station 130 and another wireless device 110 or other devices in the wireless communication system 120. In some embodiments, the CPE may be configured to communicate with the wireless device 160 using WAN signaling and to handover with the base station 130 based on such communication, rather than the wireless device 160 communicating directly with the base station 130. In an exemplary embodiment where the wireless device 160 is configured to communicate using WLAN signaling, the WLAN signal may include a WiFi or other communication signal.

[0041] Figure 2 2 is a block diagram illustrating a wireless device 200 in which aspects of the present disclosure may be implemented. In particular, a system for powering a power amplifier (PA) 244 may include envelope tracking as described in detail below. The wireless device 200 may be, for example, Figure 1 Implementations of the devices illustrated in . The described circuits may be circuits that support wireless communications. In some examples, the wireless device 200 (or any of the devices described and / or illustrated below) may be Figure 1 An example of any of the illustrated devices or any other device described herein.

[0042] Figure 2 An example of a transceiver 220 having a transmitter 230 and a receiver 250 is shown. In general, the conditioning of signals in the transmitter 230 and the receiver 250 may be performed by one or more stages of amplifiers, filters, upconverters, downconverters, etc. These circuit blocks may be associated with Figure 2 The configuration shown is arranged differently. In addition, Figure 2 Other circuit blocks not shown in FIG. 2 may also be used to condition the signals in transmitter 230 and receiver 250. Unless otherwise indicated, Figure 2 Any signal in or any other diagram in the accompanying drawings may be single-ended or differential. Figure 2 Some circuit blocks in the circuit can also be omitted.

[0043] exist Figure 2In the example shown, the wireless device 200 generally includes a transceiver 220 and a data processor 210. The data processor 210 may include a processor 296 operatively coupled to a memory 298. The memory 298 may be configured to store data and program codes, and may generally include analog and / or digital processing components. The transceiver 220 includes a transmitter 230 and a receiver 250 that support bidirectional communication. In general, the wireless device 200 may include any number of transmitters and / or receivers for any number of communication systems and frequency bands. All or a portion of the transceiver 220 may be implemented on one or more analog integrated circuits (ICs), RF ICs (RFICs), mixed signal ICs, etc.

[0044] A transmitter or receiver can be implemented using a superheterodyne architecture or a direct conversion architecture. In a superheterodyne architecture, the signal undergoes multiple stages of frequency conversion between radio frequency (RF) and baseband, such as from RF to intermediate frequency (IF) in one stage and then from IF to baseband in another stage for a receiver. In a direct conversion architecture, the signal is converted between RF and baseband in one stage. Superheterodyne and direct conversion architectures may use different circuit blocks and / or have different requirements. Figure 2 In the example shown, transmitter 230 and receiver 250 are implemented using a direct conversion architecture.

[0045] In the transmit path, the data processor 210 processes the data to be transmitted and provides in-phase (I) and quadrature (Q) analog output signals to the transmitter 230. In an exemplary embodiment, the data processor 210 includes digital-to-analog converters (DACs) 214a and 214b for converting the digital signals generated by the data processor 210 into I analog output signals and Q analog output signals (e.g., I analog output signals and Q analog output signals) for further processing. In other embodiments, the DACs 214a and 214b are included in the transceiver 220, and the data processor 210 provides data (e.g., for I and Q) to the transceiver 220 in a digital manner.

[0046] In the transmitter 230, baseband (e.g., low-pass) filters 232a and 232b filter the I and Q analog transmit signals respectively to remove the undesired image frequencies caused by the previous digital-to-analog conversion. Amplifiers (Amp) 234a and 234b amplify the signals from the baseband filters 232a and 232b respectively, and provide the I baseband signal and the Q baseband signal. The up-converter 240 with up-converting mixers 241a and 241b up-converts the I baseband signal and the Q baseband signal using the I TX LO signal and the Q TX LO signal from the transmit (TX) local oscillator (LO) signal generator 290, and provides the up-converted signal. The filter 242 filters the up-converted signal to remove the undesired image frequencies caused by the frequency up-conversion and the noise in the receive frequency band. The power amplifier 244 amplifies the signal from the filter 242 to obtain the desired output power level and provide the transmit RF signal. The transmit RF signal is routed through a duplexer or switch 246 and transmitted via an antenna 248. Although the examples discussed herein utilize I and Q signals, those skilled in the art will appreciate that the components of a transceiver may be configured to utilize polar modulation.

[0047] In the receive path, antenna 248 receives the communication signal and provides a received RF signal, which is routed through a duplexer or switch 246 and provided to a low noise amplifier (LNA) 252. Switch 246 is designed to operate with a specific RX and TX duplexer frequency separation so that the RX signal is isolated from the TX signal. The received RF signal is amplified by LNA 252 and filtered by filter 254 to obtain the desired RF input signal. Down-conversion mixers 261a and 261b in down-converter 260 mix the output of filter 254 with the I RX LO signal and Q RX LO signal (i.e., LO_I and LO_Q) from the receive (RX) LO signal generator 280 to generate an I baseband signal and a Q baseband signal. The I baseband signal and the Q baseband signal are amplified by amplifiers 262a and 262b and further filtered by baseband (e.g., low pass) filters 264a and 264b to obtain I analog input signals and Q analog input signals, which are provided to the data processor 210. In the exemplary embodiment shown, the data processor 210 includes analog-to-digital converters (ADCs) 216a and 216b for converting the analog input signals into digital signals to be further processed by the data processor 210. In some embodiments, the ADCs 216a and 216b are included in the transceiver 220 and provide data to the data processor 210 in a digital form.

[0048] exist Figure 22, TX LO signal generator 290 generates I TX LO signal and Q TX LO signal for up-conversion, while RX LO signal generator 280 generates I RX LO signal and Q RX LO signal for down-conversion. Each LO signal is a periodic signal with a specific base frequency. Phase-locked loop (PLL) 292 receives timing information from data processor 210 and generates a control signal for adjusting the frequency and / or phase of the TX LO signal from LO signal generator 290. Similarly, PLL 282 receives timing information from data processor 210 and generates a control signal for adjusting the frequency and / or phase of the RX LO signal from LO signal generator 280. PLL 292 and PLL 282 are part of a shared PLL circuit and LO generation 295 that can be shared between the TX side and the RX side of device 200.

[0049] Figure 2 200, and the configurations illustrated therein may or may not represent physical device configurations in certain specific implementations. For example, as described above, the transceiver 220 may be implemented in various integrated circuits (ICs), RF ICs (RFICs), mixed signal ICs, etc. In some embodiments, the transceiver 220 is implemented on a substrate or board (such as a printed circuit board (PCB)) having various modules, chips, and / or components. For example, the power amplifier 244, the filter 242, and the switch 246 may be implemented in separate modules or as discrete components, while the remaining components illustrated in the transceiver 220 may be implemented in a single transceiver chip.

[0050] The power amplifier 244 may include one or more stages including, for example, a driver stage, a power amplifier stage, or other components that may be configured to amplify communication signals at one or more frequencies, in one or more frequency bands, and at one or more power levels. Depending on various factors, the power amplifier 244 may be configured to operate using one or more driver stages, one or more power amplifier stages, one or more impedance matching networks, and may be configured to provide good linearity, efficiency, or a combination of good linearity and efficiency.

[0051] In some aspects using a super-heterodyne architecture, power amplifier 244 and LNA 252 (and in some examples, filters 242 and / or 254) may be implemented separately from other components in transmitter 230 and receiver 250. Although wireless device 200 describes one example of a device, it will be apparent that various aspects described herein may be implemented in other architectures (e.g., super-heterodyne architectures), and the power envelope tracking system described is not limited to, for example, Figure 2 The example architectures in FIG. 1 are power amplifiers in architectures such as those in FIG.

[0052] Figure 3A 300 is a graph illustrating tracking of a power envelope 306 for an RFFE module in accordance with various aspects described herein. As described above, the RFFE module is a wireless communication device that provides power to wireless transmit signals, and may also include elements (e.g., filters, etc.) for managing reception of wireless signals from an antenna. As part of providing power to the wireless transmit signals, the RFFE module may include a power amplifier, and may also include power management circuitry in accordance with various aspects described herein, or a connection to a power management integrated circuit (PMIC) for managing RFFE power consumption as well as power consumption of other elements of the device. Figure 3A As illustrated by power amplifier 244 of FIG. 1 , the wireless communication device includes an amplifier for controlling output power at an antenna (e.g., antenna 248). The actual power provided at the antenna as part of a transmission can vary widely based on operating conditions and specific applications. The power source for such an output power amplifier can be a significant source of wasted power, particularly when the current transmit power does not match the available power provided by the system providing power to the amplifier.

[0053] Graph 300 includes a time axis 302 and a voltage axis 301. Graph 300 illustrates example operating conditions for such an output power amplifier (e.g., power amplifier 244), with a maximum voltage 304 supported by the system, a signal 310 voltage used by the power amplifier to support a transmitted signal at a given point in time, and a voltage envelope 306 illustrating the voltage used by the signal 310 voltage to support signal performance. Gap 308 illustrates the difference between the maximum voltage 304 and the voltage envelope 306, which is associated with the voltage used by the power amplifier at a given point in time. Envelope 306 can be considered as the voltage required to support sufficient signal performance at a given point in time. If the system provides a voltage to the amplifier that is less than the voltage required by the signal 310 voltage, the integrity of the signal is destroyed and corruption of the transmitted data will result.

[0054] As the voltage provided increases, power dissipation increases, regardless of the voltage that the power amplifier actually uses to transmit the signal. Gap 308 represents excess power usage associated with the device providing a high voltage at any given time than is required to support the transmitted signal. Given the importance of power efficiency for wireless communication devices, especially mobile devices operating with limited batteries, limiting such gaps and the associated excess power dissipation is an important design goal.

[0055] Figure 3Bis a high-level block diagram of a system 350 for power envelope tracking for an RFFE module in accordance with various aspects described herein. The system 350 includes a power amplifier, which may be similar to the power amplifier 244 described above, having a circuit for limiting the power envelope tracking of the RFFE module. Figure 3B The envelope tracking power source 358 dissipates excess power associated with the gap 308).

[0056] To perform envelope tracking and match the voltage provided to the power amplifier 390 to the voltage used by the signal at a given time, the baseband transmitter 351 provides signal samples 352 to an envelope detector 353. The envelope detector 353 outputs envelope values ​​to a shaping table 354 which outputs an envelope signal 356. The envelope signal 356 is input to a power source 358 and used along with power from a battery 357 to match the voltage associated with the envelope of the transmit signal to the voltage provided to the power amplifier 390.

[0057] When the envelope signal 356 is provided to the power source 358, the trigger input 368 from the envelope detector 353 is used to align the timing of the analog envelope signal and the voltage provided from the power source 358 with the RF input 360 signal provided to the power amplifier 390 and the associated transmit signal at the RF output 398. The RF input 360 is generated by the RF vector signal generator 380, which includes a waveform generator 382 and an RF upconverter 384. The waveform generator 382 generates a low frequency version of the waveform to be transmitted from the samples provided by the baseband transmitter 351. In other embodiments, the transmitter of the wireless device 200 or another such device can generate the waveform. The low frequency waveform is upconverted to the transmit frequency by the RF upconverter 384 and is provided to the RF input 360 for amplification by the power amplifier 390.

[0058] The voltage provided to PA 390 by envelope tracking power source 358 can thus match Figure 3A 306. The timing alignment 359 between the envelope signal 356 and the RF input 360 prevents the envelope 306 from being misaligned with the signal 310, which would result in signal clipping and errors at the RF output 398 (e.g., if the envelope 306 shifts to the left or right while the signal 310 maintains position). Additional details related to specific implementations of the timing alignment 359 and the envelope tracking power source 358 according to various aspects described herein are provided below.

[0059] Figure 4 is a block diagram illustrating aspects of a system 400 for controlling power provided to an RFFE power amplifier using power envelope tracking according to aspects described herein. The system 400 may be Figure 3B4. The system 400 is a specific implementation of an envelope tracking power source 358, wherein the envelope signal 356 is provided to the envelope tracking power source 358 as a digital envelope signal 410. In the system 400, the digital envelope signal 410 is provided to a digital-to-analog converter (DAC) 420, which outputs an analog envelope signal 410. The analog envelope signal 410 is provided to a supply source 430, which outputs a voltage VCC 432 that matches the envelope of the RF signal provided at the RF transmit signal input 460 and is synchronized and causes the VCC provided to the power amplifier 450 to match the voltage required at the RF transmit signal output 462.

[0060] During operation, control circuit 440 may change operating settings of power amplifier 450 depending on the dynamic range or operating conditions present in the signal provided at input 460. Similarly, in various implementations described below, supply source 430 may include various structures for responding to the details of a particular transmit signal. For example, in one implementation, analog envelope signal 410 may be provided to an amplifier that outputs a signal that tracks the dynamic aspects of voltage 432, wherein a sensing circuit is coupled to the output of the amplifier to track the DC aspects of voltage 432. A switch may be used to set the DC level of voltage 432, and the output of the switch and amplifier may be combined to provide voltage 432 at a level that tracks the envelope of the signal being amplified by power amplifier 450. In various implementations, additional circuits may be included in system 400, such as additional control circuits for responding to device operating conditions, protection circuits, signal interference suppression circuits to minimize the propagation of stray signals through the voltage source, or other such circuits.

[0061] In some implementations, the control circuit 440 may include a boost converter, or other such elements may be used to manage voltage when the battery level is low in accordance with the aspects described herein. The aspects described herein, although not specifically exemplified with such boost converter elements, may include additional battery level and power management features in conjunction with the aspects described herein to manage power usage at all stages of the battery power level for a device including the aspects described herein.

[0062] Figure 5 is a block diagram illustrating aspects of a system 500 for controlling power provided to an RFFE power amplifier 450 using power envelope tracking in accordance with aspects described herein. Figure 5 In the illustrated example, the RF input 460, the RF output 462 and the power amplifier 450 are connected to Figure 4Envelope tracking power source 520 illustrates a specific implementation of envelope tracking power source 358 or system 400 where digital-to-analog circuit 510 is external to envelope tracking power source 520 (eg, as compared to DAC 420 included in system 400 ).

[0063] The envelope tracking power source 520 includes at least two amplifiers as part of an amplifier circuit 524. Figure 5 In the illustrated example of , the amplification circuit 524 includes a first amplifier 528 and a second amplifier 526. As described above, the DAC 510 can receive a digital envelope signal and provide an analog envelope signal to the envelope tracking power source 520 at the input port 511. The input port 511 is coupled to the input interface circuit 522. The input interface circuit provides both a tracking signal that matches the analog envelope signal and a control input to the amplification circuit 524.

[0064] In some implementations, the first amplifier 528 can be a main amplifier that tracks the analog envelope signal itself under standard or low demand operating conditions. The second amplifier 526 can be a peaking amplifier that is turned off during low demand or standard operating conditions, but is turned on to support peak voltage conditions, high frequency envelope changes, or other operating conditions that exceed the response capabilities of the first amplifier 528 operating alone. The second amplifier can be set to an off condition when standard operating conditions exist, and turned on when needed by a control signal from the amplifier control circuit 536. In some implementations, the control signal can be generated by the amplifier control circuit 536 integrated with the modem based on the characteristics of the analog envelope signal provided to the input port 511 via the DAC 510. In other implementations, the amplifier control circuit 536 can be configured as a feedback circuit that receives a signal from the conditioning circuit 534. In other implementations, the input interface circuit 522 can integrate the control circuit 536 to provide a control input terminal for the second amplifier 526. In any case, the processing circuitry may provide a control signal indicative of a condition for setting the second amplifier 526 to an on-state or an off-state based on the characteristics of the analog envelope signal.

[0065] In some implementations, the control signal from the amplifier control circuit is a binary on / off signal. In some implementations, other non-binary control signals may be used. In some implementations, multiple modes of peaking amplifier operation may be used, such as a low power mode, a high power mode, or other such modes. In such implementations, the slope of the RF signal, the radio access technology (RAT) configuration, the bandwidth of the RF signal, the peak-to-average power ratio (PAPR) of the signal, or other values ​​may be used to select an operating mode and / or determine the structure of the control signal provided by the control circuit that manages the peaking amplifier 526.

[0066] The first amplifier 528 has an input and an output, wherein the input is coupled to the tracking signal from the input interface circuit 522 and the output provides a voltage signal to the output filter 542. During operating conditions where the second amplifier 526 is in an off state, the output of the first amplifier 528 provides a voltage output to the output filter 542, which can filter any stray signals or reduce noise from the output of the first amplifier 528. The voltage signal output from the output filter 542 is then provided as the dynamic portion of the VCC voltage provided to the power amplifier 450 via the output port 551 of the envelope tracking power source 520. The output of the first amplifier 528 is additionally tapped by a connection to a sensing element 530. The sensing element 530 provides a value that tracks the output signal from the first amplifier 528 to the sensing and conditioning circuit 534. The sensing and conditioning circuit 534 can provide feedback to the envelope amplifier circuit 524 via the amplifier control circuit 536 to adjust the control settings, and can also provide a direct current (DC) control signal that tracks the DC portion of the target VCC value to be output at the output port 551. The sensing and conditioning circuit may additionally provide input to switch 540 to enhance DC control. The input from sensing and conditioning circuit 534 to switch 540 is combined with the VCC level signal from the modem to manage DC control tracking. These two signals are input to switch 540, which outputs the DC portion of the VCC value via element 546. In some specific implementations, element 546 may be an inductor configured to filter noise from the DC portion of the VCC value. In other specific implementations, a more complex filtering circuit may be used at the output of switch 540. The combined output of switch 540 and output filter 542 provides a VCC voltage value at output port 551, which tracks the voltage used by power amplifier 450 to create a transmit RF signal to be transmitted via an antenna at RF output 462. As described above, adjusting the VCC value for power amplifier 450 reduces unnecessary power dissipation that occurs when the VCC value provided to power amplifier 450 is significantly greater than the VCC value required for the transmit signal.

[0067] As described above, when the second amplifier 526 is off, the output from the second amplifier does not contribute to the VCC value provided to the output port 551 and the power amplifier 450. When the amplifier circuit 536 determines that the first amplifier 528 cannot track the envelope signal to provide an acceptable voltage at the output port 551, the second amplifier 526 is set to the on state and operates similarly to the output path from the first amplifier 528. The peaking input signal is provided to the input of the second amplifier, and the peaking voltage signal is output from the output of the second amplifier 526. The peaking voltage signal is filtered by the output filter 544 and combined with the voltage signal from the switch 540 and the output filter 542 (e.g., from the first amplifier 528). When combined with other signals, the peaking voltage signal can provide higher performance responsiveness and / or power compared to operation without the peaking voltage signal from the second amplifier 526. Similarly, a sensing element 532 tapped at a signal from the output of the second amplifier 526 is provided to a circuit 534 and both a DC control signal provided to the switch 540 and a feedback signal processed via a feedback circuit implemented as an amplifier control circuit 536 can be updated or modified based on the characteristics of the peaking voltage signal from the output of the second amplifier 526.

[0068] Additionally, a configuration option of setting the second amplifier 526 to an off state saves power such that the power consumed by the second amplifier 526 is less than the power consumed by the amplification circuit 524, where a single linear amplifier is combined with any excess power dissipation caused by the additional voltage headroom (e.g., a larger gap, such as gap 308) provided to the power amplifier 450 via the output port 551.

[0069] As described above, in various implementations, the control circuit 536 can be used to manage the addition of the second amplifier 526 (e.g., a peaking amplifier) ​​to the circuit that contributes to the voltage, provided that the power amplifier 450 can be controlled in different ways. In some implementations, the input interface circuit 522 includes a control circuit to monitor the most significant bit provided to the DAC 510 using the input of the digital envelope signal. When the most significant bit is valid (e.g., indicating a high voltage value), the second amplifier 526 can be turned on. In still other implementations, the most significant bit of the digital envelope signal can be used directly to turn on the peaking second amplifier 526 without additional processing circuitry. In some implementations, a control signal can be provided from the modem circuit based on envelope tracking data synchronized with the control of the second amplifier 526 to determine when to turn the second amplifier on or off.

[0070] In some implementations, the control circuit 536 is implemented using a feedback connection directly from the sense amplifier and conditioning circuit 534. Such feedback signals from the conditioning circuit 534 have the benefit of being tightly coupled to the voltage signal. Under high frequency operation, such tight feedback connections can improve the tracking of the envelope to the transmitted signal, limit errors or noise in the difference between the envelope and the transmitted signal, and allow for smaller gaps (e.g., gap 308), where the dissipated power is reduced in association with the gap between the voltage provided to the power amplifier and the voltage used by the power amplifier. Using feedback directly from the conditioning circuit, the current, voltage, or power directly from the first amplifier 528 or the second amplifier 526 can be directly measured and compared to the target envelope match. Such feedback can be used to directly determine the control set point of the amplifier operation (e.g., the second amplifier is turned on and off), and directly correct the mismatch between the expected output and the voltage value at the output port 551. As described above, in some implementations, the control signal from the amplifier control circuit is a binary on / off signal. In some implementations, other non-binary control signals can be used. In some implementations, multiple modes of peaking amplifier operation may be used, such as a low power mode, a high power mode, or other such modes. In such implementations, the slope of the RF signal or the peak-to-average power ratio (PAPR) of the signal may be used to select an operating mode and / or determine the structure of a control signal provided by a control circuit that manages the peaking amplifier 526.

[0071] In some implementations, the use of a second amplifier 526 in parallel with the first amplifier 528 allows for different configurations for different applications. In some implementations, the first amplifier 528 and the second amplifier 526 have similar or identical interfaces, where the input interface circuit 522 is replicated for both amplifiers. Figure 6 In other implementations discussed, different amplifiers are used and may be configured based on the specific characteristics of each amplifier. For example, in some implementations, rather than using a control signal to turn the second amplifier 526 on and off, in some implementations, two separate signals may be provided to the input interface circuit 522, one derived from the most significant bit of the digital envelope signal and one derived from the least significant bit of the digital envelope signal. The signal derived from the most significant bit may drive the second amplifier 526, and the signal derived from the least significant bit may drive the first amplifier 528. In other implementations, the modem may provide separate signals for different amplifiers of the amplification circuit 524.

[0072] In some such implementations, the second amplifier 526 can have lower linearity because it operates at a higher output range, and the first amplifier 528 can have greater linearity for operating at the lower output range.

[0073] Figure 6 is a block diagram illustrating aspects of a system 600 for controlling power provided to an RFFE power amplifier using power envelope tracking in accordance with aspects described herein. System 600 includes the same DAC 510 and power amplifier 450, as well as the same sensing, conditioning, filtering, and switching circuits, but Figure 5 The envelope amplifier circuit 524 is Figure 6 The different envelope amplifier circuits 624 in are replaced. Figure 6 The envelope amplifier circuit 624 includes a common stage 625 and separate amplifiers 626 and 628 with independent control inputs. In some implementations, the common stage 625 can be removed, where the input interface circuit 522 provides separate signals to the separate amplifiers 626 and 628. In some implementations, the common stage 625 can be integrated with the input interface circuit 522 to provide a smooth or other interface integration between the digital signal output by the amplifier circuit 524 and the analog signal.

[0074] exist Figure 5 In a specific implementation, the input interface circuit 522 can operate as a digital divider between the envelope signal provided to the envelope tracking power source 520 and the amplification circuit 524. Figure 6 624. In some embodiments, the common stage 625 can be used as an additional analog division at the input of the amplifier circuit 624. In some configurations, the amplifier design of the amplifier circuit 624 is used for a multi-stage circuit. Some such circuits include smoothing functions to manage filtering or interface various aspects of the amplifier to the digital input. In some specific implementations, the common stage 625 can provide signal performance benefits that manage such smoothing of the signal and manage the signal input to the separate amplifiers 626 and 628.

[0075] In some implementations, amplifier 628 may be similar to Figure 5 The first amplifier 528 and the amplifier 626 may be similar to Figure 5526. In some implementations, amplifier 628 may be a class AB amplifier (e.g., an amplifier with greater linearity) and the second amplifier may be a class C amplifier, thereby providing design flexibility and component options while maintaining envelope tracking performance. In some implementations, the second amplifier 626 operating as a peaking amplifier may be a switch mode amplifier, such as a class E amplifier, a class G amplifier, or a class H amplifier. Some such amplifiers may, for example, be used in a switching configuration, such as when the most significant bit is used as a threshold or other bits are used with a threshold circuit to activate the second amplifier 626 operating in saturation as a threshold activated switching amplifier to achieve high efficiency. In such implementations, the first amplifier 628 may provide any desired linearity, with the second amplifier 626 operating only in saturation to provide the boost required to achieve higher voltage levels at the output port 551 and the corresponding connection to the power amplifier 450.

[0076] Figure 7 is a block diagram illustrating aspects of a system 700 for controlling power provided to an RFFE power amplifier using power envelope tracking in accordance with aspects described herein. The system 700 includes the same DAC 510 and power amplifier 450, but the separate sensing and filtering elements are combined into a shared sensing element 730 having a common output to an output filter 744 that provides a combined variable voltage signal at its output combined with a low frequency (e.g., DC) voltage from a switch 540. The combined sensing element 730 can be used in environments with space or component level constraints for sensing elements. In some implementations, the output filter 744 can be external to the IC system for envelope tracking power source 720. For example, in some implementations, the output filter 744 can be a capacitor on a support plate coupled to the amplification circuit 524.

[0077] In some implementations, the sensing element 730 may be a simple resistive element used to sense current and voltage and turn on the switch 540 (e.g., a switching regulator that provides DC and low frequency components of the envelope tracking voltage for the power amplifier 450). In various implementations, the output signal of the amplifier circuit 524 is not used as an input to the conditioning circuit 734, but rather a replica signal (e.g., from a replica circuit, which is not shown) is used to manage the switch 540 and any feedback as a signal from the control circuit 536 to avoid affecting the higher frequency voltage signal (e.g., the portion of the signal not provided by the switch 540). This system may additionally operate to separate the switch 540, which has switching energy, from the element 546 (e.g., an inductor) which has energy that may cause problems if pushed into the power amplifier 450. In many implementations, the switch 540 may operate at high efficiency but may not provide accurate high frequency voltage signals and tracking (e.g., due to device limitations). When the frequency and power levels are lower, the switch 540 may provide voltage to the power amplifier 450 at high efficiency. As the frequency and power level of power amplifier 450 increases, the switch is no longer able to meet the voltage tracking constraints and the power assist of the amplifier is used at a lower efficiency to meet the voltage tracking at the higher power and frequency levels. Additional efficiency is achieved by pushing the DC power to switch 540. As the power demand on the linear assist from the first amplifier increases, the efficiency decreases, and the addition of the second amplifier as a peaking amplifier allows the first linear amplifier to operate in a high efficiency state where, in addition to efficiently providing the DC voltage by switch 540, the peaking amplifier also operates efficiently for the different purpose of efficiently providing the peaking voltage (e.g., so that the amplifier circuit including the linear amplifier does not need to inefficiently provide any DC power).

[0078] Figure 8 8 is a block diagram illustrating aspects of a system 800 for controlling power provided to an RFFE power amplifier using power envelope tracking according to aspects described herein. The system 800 includes Figure 5Same DAC and envelope tracking, but with direct feedback circuit 836 from conditioning circuit 534 as shown, and additional system elements of transceiver 808, modem 820, and coupler 830. Coupler 830 can provide a feedback signal describing the operation of power amplifier 450, which can be used as additional feedback to improve the envelope signal, and provide management of the control input to prevent the amplification circuit of the envelope tracking power source from wasting power into power amplifier 450 due to excessive current. The series feedback from coupler 830 can allow the amplification circuit to provide a voltage that tracks the envelope, where the current required by power amplifier 450 comes from a more efficient source in the form of switch 540 (e.g., because the PA presents a high resistance, rather than a low resistance in the range of 10 ohms, which would require a large current to maintain the envelope tracking voltage). Coupler 830 can provide feedback via feedback circuit 810 of transceiver 808 coupled with control from the modem to provide a signal to switch 540 to efficiently provide the current required for the operation of power amplifier 450 (e.g., matching the tracking envelope).

[0079] In some implementations, various control and feedback loops (including control of the amplification circuitry within the envelope tracking power source and feedback from the coupler 830 to the feedback circuit 810) may be calibrated as follows. Given a voltage envelope (e.g., 100 MHz frequency at low voltage levels), a first (e.g., main) amplifier may be enabled and performance (e.g., envelope tracking performance) calculated. A second (e.g., peaking) amplifier may then be enabled with the first amplifier disabled, and both may then be enabled. The control circuitry, circuitry, input interface circuitry, feedback circuitry 836, or any other such circuitry within the modem may use the performance information at a given frequency for initial calibration. Such calibration may be performed for frequency distributions used or desired for any communications band to set initial feedback settings. The feedback system may then be adjusted during operation to manage performance during operation of a device using any of the systems described herein.

[0080] Fig. 9 is a flow chart describing an example of the operation of a method 900 for operating an apparatus including an envelope tracking power source for a power amplifier. The blocks in the method 900 may or may not be performed in the order shown, and in some embodiments, may be performed at least partially in parallel.

[0081] At block 902 of method 900 , a device (or a component thereof) may calculate (eg, via control circuitry of a modem) envelope information for a transmit signal.

[0082] At block 904 of method 900 , a device or component of a device may generate (eg, via a radio frequency front end (RFFE)) a transmit signal.

[0083] At box 906 of method 900, the device or component of the device may provide a voltage to a power amplifier of the RFFE via an envelope tracking power source. Such an envelope tracking power source may be any envelope tracking power source described herein. In one specific implementation, the envelope tracking power source includes: an envelope signal input port, the envelope signal input port being configured to receive an envelope tracking signal generated based on envelope information; an output power port, the output power port being configured to provide the voltage to the power amplifier; a first amplifier, the first amplifier having an input and an output; a second amplifier, the second amplifier having an input, an output, and a control input, wherein the control input of the second amplifier is configured to program the second amplifier based on a current operating mode selected from a plurality of operating modes; an input interface circuit, the input interface circuit having an input coupled to the envelope signal input port, a control input coupled to the first amplifier, and a control input coupled to the second amplifier. a first output terminal coupled to the input terminal of the first amplifier and a second output terminal coupled to the input terminal of the second amplifier; a sensing and conditioning circuit having an output terminal and one or more input terminals coupled to the output terminal of the first amplifier and the output terminal of the second amplifier; a switching circuit having an input terminal and an output terminal, wherein the input terminal is coupled to the output terminal of the sensing and conditioning circuit, and wherein the output terminal is coupled to the output power port; and an output filter circuit, wherein the output terminal of the first amplifier is coupled to the output power port via the output filter circuit, and wherein the output terminal of the second amplifier is coupled to the output power port via the output filter circuit.

[0084] Fig.10 1000 is a functional block diagram of an apparatus including an envelope tracking supply source for a power amplifier as described herein. Apparatus 1000 includes component 1002 for calculating envelope information for a transmitted signal. In some aspects, component 1002 is a modem, such as Fig.12 1204, or other such controls or communication circuits of a wireless communication device as described herein. Device 1000 also includes component 1004 for generating a transmit signal (e.g., for use in determining envelope information by component 1002). Device 1004 can be a circuit of a transceiver (such as transceiver 1206) that provides a signal to an RFFE, an element of transmitter 230, or other such element of a wireless communication path as described herein. Device 1000 includes component 1006 for providing an envelope tracking voltage to power a power amplifier that amplifies the transmit signal. Component 1006 can be an envelope tracking power source as described herein or an element of an envelope tracking power source, such as supply source 430, envelope tracking power source 520, system 600, system 700, envelope tracking power source 720, system 800, or any such component described herein.

[0085] Fig.11 1 is a diagram illustrating an exemplary environment 1100 including an electronic device 1102 and a base station 1104, each of which includes a transceiver (e.g., a wireless transceiver 1122 of the electronic device 1102) or a receiver having a receive path that may include a specific implementation of an envelope tracking power source according to examples described herein. In the environment 1100, the electronic device 1102 communicates with the base station 1104 via a wireless communication link 1106 (wireless link 1106). In such an example, the electronic device 1102 is depicted as a smart phone. However, the electronic device 1102 can be implemented as any suitable computing or other electronic device, such as a cellular base station, a broadband router, an access point, a cellular or mobile phone, a gaming device, a navigation device, a media device, a laptop computer, a desktop computer, a tablet computer, a server, a network attached storage (NAS) device, a smart appliance, a vehicle-based communication system, an Internet of Things (IoT) device, etc.

[0086] Base station 1104 communicates with electronic device 1102 via wireless link 1106, which can be implemented as any suitable type of wireless link. Although depicted as a base station tower of a cellular radio network, base station 1104 can represent or be implemented as another device, such as a satellite, a cable TV headend, a terrestrial television broadcast tower, an access point, a peer device, a mesh network node, a router, a fiber optic line, generally another electronic device, etc. Thus, electronic device 1102 can communicate with base station 1104 or another device via a wired connection, a wireless connection, or a combination thereof.

[0087] The wireless link 1106 may include a downlink of data or control information communicated from the base station 1104 to the electronic device 1102, and an uplink of other data or control information communicated from the electronic device 1102 to the base station 1104. The wireless link 1106 may use any suitable communication protocol or standard (such as 3rd Generation Partnership Project Long Term Evolution (3GPP LTE), 5G New Radio (3GPP 5GNR), IEEE 802.11, IEEE 802.16, Bluetooth TM etc.) to achieve this.

[0088] The electronic device 1102 includes a processor 1108 and a computer-readable storage medium 1110 (CRM 1110). The processor 1108 may include any type of processor configured to execute processor-executable instructions (e.g., code) stored by the CRM 1110, such as an application processor or a multi-core processor. The CRM 1110 may include any suitable type of data storage medium, such as volatile memory (e.g., random access memory (RAM)), non-volatile memory (e.g., flash memory), optical media, magnetic media (e.g., disk or tape), etc. In the context of the present disclosure, the CRM 1110 is implemented to store instructions 1112, data 1114, and other information of the electronic device 1102, and therefore does not include transient propagating signals or carrier waves.

[0089] The electronic device 1102 may also include an input / output port 1116 (I / O port 1116) or a display 1118. The I / O port 1116 enables data exchange or interaction with other devices, networks, or users. The I / O port 1116 may include a serial port (e.g., a universal serial bus (USB) port), a parallel port, an audio port, an infrared (IR) port, and the like. The display 1118 may be implemented as a screen or projection that presents graphics of the electronic device 1102, such as one or more graphic images, such as a user interface associated with an operating system, program, or application. Alternatively or in addition, the display 1118 may be implemented as a display port or a virtual interface through which the graphical content of the electronic device 1102 is communicated or presented.

[0090] For communication purposes, the electronic device 1102 also includes a modem 1120, a wireless transceiver 1122, and at least one antenna 1130. The wireless transceiver 1122 includes a converter unit (CU) 1124 and a transceiver (TRX) unit 1126. The wireless transceiver 1122 uses RF wireless signals to provide connectivity to a corresponding network and other electronic devices connected thereto. Additionally or alternatively, the electronic device 1102 may include a wired transceiver (such as an Ethernet or fiber optic interface) for communicating through a personal or local network, an intranet, or the Internet. The wireless transceiver 1122 can facilitate communication over any suitable type of wireless network, such as a wireless local area network (LAN) (WLAN) (such as WI-Fi or Bluetooth), a peer-to-peer (P2P) network, a mesh network, a cellular network (e.g., 3GPP2, 4G LTE, 5G NR or other cellular network), a wireless wide area network (LTE) (e.g., based on 3GPP2, 4G LTE, 5G NR, etc.), a navigation network (e.g., the Global Positioning System (GPS) or another Satellite Positioning System (SPS) in North America), and / or a wireless personal area network (WPAN). In the context of the exemplary environment 1100, the wireless transceiver 1122 enables the electronic device 1102 to communicate with the base station 1104 and the network connected thereto. Other figures referenced herein may relate to other wireless networks.

[0091] The modem 1120 (such as a baseband modem) can be implemented as a system on chip (SoC) that provides a digital communication interface for data, voice, messaging, and other applications of the electronic device 1102. The modem 1120 may also include baseband circuits to perform high-rate sampling processes, which may include analog-to-digital conversion (ADC), digital-to-analog conversion (DAC), gain correction, tilt correction, frequency conversion, etc. The modem 1120 may also include logic to perform in-phase / quadrature (I / Q) operations, such as synthesis, encoding, modulation, demodulation, and decoding. More generally, the modem 1120 may be implemented as a digital signal processor (DSP) or a processor configured to perform signal processing to support communication via one or more networks. Alternatively, the ADC or DAC operations may be performed by a separate component or another illustrated component (such as a wireless transceiver 1122).

[0092] The wireless transceiver 1122 may include circuits, logic, and other hardware for sending or receiving wireless signals for at least one communication frequency band. In operation, the wireless transceiver 1122 may implement at least one radio frequency transceiver unit to process data and / or signals associated with the communication data of the electronic device 1102 via the antenna 1130. Generally speaking, the wireless transceiver 1122 may include filters, switches, amplifiers, etc. for routing and processing signals sent or received via the antenna 1130. Generally speaking, the wireless transceiver 1122 includes multiple transceiver units (e.g., for different wireless protocols such as WLAN and WWAN, or for supporting different frequency bands or frequency band combinations).

[0093] In one example, the filters, switches, amplifiers, mixers, etc. of the wireless transceiver 1122 may include at least one single-ended amplifier, a switching circuit, at least one transformer, at least one differential amplifier, and at least one mixer. In some implementations, a single-ended amplifier that amplifies the strength of a signal is coupled to the antenna 1130. Therefore, in addition to increasing the strength of the signal, the single-ended amplifier can also couple the wireless signal to the antenna 1130 or couple the wireless signal from the antenna. In some implementations, the switching circuit can switchably couple each transformer in a set of transformers to the single-ended amplifier. The set of transformers provides physical or electrical isolation between the single-ended amplifier and other circuits of the wireless transceiver 1122. The set of transformers also regulates the signal propagated through the set of transformers. The output of the transformer can be coupled to one or more mixers.

[0094] Some examples may use a differential amplifier at the output of the transformer before the signal is input to the mixer. In such an example, the differential amplifier (similar to a single-ended amplifier) ​​enhances the strength of the propagating signal. The wireless transceiver may also perform frequency conversion using a composite signal and a mixer. The mixer may include an up-converter and / or down-converter that performs frequency conversion in a single conversion step or through multiple conversion steps. The wireless transceiver 1122 may also include logic (not shown) that performs in-phase / quadrature (I / Q) operations using the composite signal, such as synthesis, encoding, modulation, demodulation, and decoding.

[0095] In some cases, the components of the wireless transceiver 1122 or its transceiver unit 1126 are implemented as separate receiver and transmitter entities. Additionally or alternatively, the wireless transceiver 1122 can be implemented using multiple or different parts to implement corresponding receiving and transmitting operations (e.g., using separate transmission chains and receiving chains). An example implementation of the transceiver unit 1126 is described above. In addition, different wireless protocols such as WWAN and WLAN can be implemented on separate chips or as separate systems on chips (SOCs). Thus, blocks such as modems 1120 and transceivers 1122 can represent more than one modem 1120 or transceiver implemented together on separate chips or separate SOCs.

[0096] The apparatus implementing the circuits described herein may be a stand-alone device or may be part of a larger device. The device may be (i) a stand-alone IC, (ii) a collection of one or more ICs that may include a memory IC for storing data and / or instructions, (iii) an RFIC such as an RF receiver (RFR) or RF transmitter / receiver (RTR) or corresponding mmW components, (iv) an ASIC such as a mobile station modem (MSM), (v) a module that may be embedded in other devices, (vi) a receiver, a cellular phone, a wireless device, a handset or a mobile unit, (vii) and the like.

[0097] Fig.12 1 is a diagram illustrating an exemplary electronic device 1202 according to examples described herein, the exemplary electronic device including a transceiver 1206, which may include and / or implement a dynamic voltage source for a power amplifier using envelope tracking. As shown, in addition to an integrated circuit 1210, the electronic device 1202 also includes an antenna 1204, a transceiver 1206, and a user input / output (I / O) interface 1208. The illustrated example of the integrated circuit 1210 or its core includes a microprocessor 1212, a graphics processing unit (GPU) 1214, a memory array 1216, and a modem 1218. Each component is operably coupled to another component, such as the GPU 1214 is operably coupled to the user I / O interface 1208.

[0098] The electronic device 1202 may be a mobile or battery-powered device or a stationary device designed to be powered by a power grid. Examples of electronic devices 1202 include server computers, network switches or routers, blades in a data center, personal computers, desktop computers, notebooks or laptop computers, tablet computers, smart phones, entertainment devices, or wearable electronic devices such as smart watches, smart glasses, or clothing articles. The electronic device 1202 may also be a device or a portion thereof with embedded electronic devices. Examples of electronic devices 1202 with embedded electronic devices include passenger vehicles, industrial equipment, refrigerators or other household appliances, drones or other unmanned aerial vehicles (UAVs), or power tools.

[0099] For electronic devices with wireless capabilities, the electronic device 1202 includes an antenna 1204 that is coupled to a transceiver 1206 to enable reception or transmission of one or more wireless signals. An integrated circuit 1210 can be coupled to the transceiver 1206 to enable the integrated circuit 1210 to access received wireless signals or provide wireless signals for transmission via the antenna 1204. The electronic device 1202 shown also includes at least one user I / O interface 1208. Examples of user I / O interface 1208 include a keyboard, a mouse, a microphone, a touch-sensitive screen, a camera, an accelerometer, a tactile mechanism, a speaker, a display screen, or a projector. According to the examples described herein, the transceiver 1206 may correspond to, for example, (e.g., Fig.11 ) wireless transceiver 1122 and may include an RF power sensor.

[0100] Integrated circuit 1210 may include, for example, one or more instances of a microprocessor 1212, a GPU 1214, a memory array 1216, a modem 1218, and the like. Microprocessor 1212 may be used as a central processing unit (CPU) or other general-purpose processor. Some microprocessors include different components, such as multiple processing cores, which can be powered on or off individually. GPU 1214 may be particularly suitable for processing visual-related data for display, such as video data images. If visual-related data is not rendered or otherwise processed, GPU 1214 may be fully or partially powered off. Memory array 1216 stores data for microprocessor 1212 or GPU 1214. Exemplary types of memory for memory array 1216 include random access memory (RAM), such as dynamic RAM (DRAM) or static RAM (SRAM); flash memory; and so on. If a program does not access data stored in memory, memory array 1216 may be powered off as a whole or block by block. Modem 1218 demodulates the signal to extract the encoded information, or modulates the signal to encode information into the signal. If there is no information to be decoded from the inbound communication or encoded for the outbound communication, the modem 1218 can be idle to reduce power consumption. Integrated circuit 1210 can include additional or alternative components other than those shown, such as I / O interfaces, sensors (such as accelerometers), another part of the transceiver or receiver chain, a custom or hard-coded processor (such as an application specific integrated circuit (ASIC)), and the like.

[0101] Integrated circuit 1210 may also include a system on chip (SoC). An SoC may integrate a sufficient number of different types of components to enable the SoC to provide computing functionality such as a notebook computer, a mobile phone, or another electronic device using at least one chip. The components of an SoC or integrated circuit 1210 may generally be referred to as cores or circuit blocks. Examples of cores or circuit blocks include Fig.12 In addition to those illustrated in the examples, a voltage regulator, a main memory or cache memory block, a memory controller, a general purpose processor, an encryption processor, a video or image processor, a vector processor, a radio component, an interface or communication subsystem, a wireless controller or a display controller may also be included. Any of these cores or circuit blocks (such as a central processing unit or a multimedia processor) may also include multiple internal cores or circuit blocks.

[0102] While selected aspects have been illustrated and described in detail, it should be understood that various substitutions and changes may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

[0103] Exemplary aspects of the present disclosure include, but are not limited to:

[0104] Aspect 1. An envelope tracking power source, the envelope tracking power source comprising: an envelope signal input port; an output power port; a first amplifier, the first amplifier having an input and an output; a second amplifier, the second amplifier having an input, an output, and a control input, wherein the control input of the second amplifier is configured to set a power state for the second amplifier; an input interface circuit, the input interface circuit having an input coupled to the envelope signal input port, a first output coupled to the input of the first amplifier, and a second output coupled to the input of the second amplifier; a sensing and conditioning circuit, the sensing and conditioning circuit having an output and one or more inputs coupled to the output of the first amplifier and the output of the second amplifier; a switching circuit, the switching circuit having an input and an output, wherein the input is coupled to the output of the sensing and conditioning circuit, and wherein the output is coupled to the output power port; and an output filter circuit, wherein the output of the first amplifier is coupled to the output power port via the output filter circuit, and wherein the output of the second amplifier is coupled to the output power port via the output filter circuit.

[0105] Aspect 2. The envelope tracking power source according to aspect 1, wherein the first amplifier is a main amplifier configured to provide linear amplification.

[0106] Aspect 3. An envelope tracking power source according to any one of aspects 1 to 2, wherein the control input configures the power state for the second amplifier by switching the second amplifier between an on state and an off state.

[0107] Aspect 4. The envelope tracking power source according to any one of aspects 1 to 3, wherein the second amplifier is a peaking amplifier.

[0108] Aspect 5. An envelope tracking power source according to any one of aspects 3 to 4, wherein the second amplifier is configured to operate in a saturation mode during the on-state.

[0109] Aspect 6. The envelope tracking power source according to any one of aspects 1 to 5, wherein the control input configures the power state based on a current operating mode selected from a plurality of operating modes.

[0110] Aspect 7. The envelope tracking power source according to aspect 6, wherein the plurality of operating modes include a high power mode and a low power mode.

[0111] Aspect 8. An envelope tracking power source according to any one of Aspects 1 to 7, wherein the control input is further based on one or more of a radio access technology (RAT) configuration, a peak-to-average power ratio of a radio frequency (RF) signal, and a bandwidth of the RF signal.

[0112] Aspect 9. An envelope tracking power source according to any one of Aspects 1 to 8, wherein the envelope tracking power source also includes a feedback circuit coupled between the sensing and conditioning circuit and the control input terminal of the second amplifier, wherein the feedback circuit provides a feedback signal from the sensing and conditioning circuit to the control input terminal to adjust the match between the power demand of the power amplifier coupled to the output power port and the voltage provided by the switching circuit, the first amplifier and the second amplifier at the output power port.

[0113] Aspect 10. An envelope tracking power source according to any one of Aspects 1 to 9, wherein the envelope tracking power source further includes: a first sensing element coupled between the output of the first amplifier and the input of the sensing and conditioning circuit; and a second sensing element coupled between the output of the second amplifier and the second input of the sensing and conditioning circuit.

[0114] Aspect 11. An envelope tracking power source according to any one of Aspects 1 to 9, wherein the envelope tracking power source further includes: a first sensing element coupled between the output of the first amplifier and the input of the sensing and conditioning circuit; and a second sensing element coupled between the output of the second amplifier and the second input of the sensing and conditioning circuit.

[0115] Aspect 12. An envelope tracking power source according to any one of Aspects 1 to 9, wherein the envelope tracking power source further comprises: a sensing element having an input and an output, wherein the input is coupled to the output of the first amplifier and the output of the second amplifier, and wherein the output is coupled to the input of the sensing and conditioning circuit.

[0116] Aspect 13. An envelope tracking power source according to any one of Aspects 1 to 12, wherein the output filter circuit includes a first filter circuit coupled between the output end of the first amplifier and the output power port; wherein the output filter circuit also includes a second filter circuit different from the first filter circuit, wherein the second filter circuit is coupled between the output end of the second amplifier and the output power port.

[0117] Aspect 14. An envelope tracking power source according to any one of aspects 1 to 13, wherein the first amplifier is a class AB amplifier, and wherein the second amplifier is a class C amplifier.

[0118] Aspect 15. The envelope tracking power source according to any one of aspects 1 to 13, wherein the first amplifier is a linear amplifier.

[0119] Aspect 16. The envelope tracking power source according to any one of aspects 1 to 13, wherein the second amplifier is a switching amplifier.

[0120] Aspect 17. An envelope tracking power source according to any one of Aspects 1 to 16, wherein the input interface circuit is configured to receive a digital envelope signal at the envelope signal input port; wherein the input interface circuit is configured to output a first tracking signal at the first output terminal based on a set of least significant bits of the digital envelope signal; and wherein the input interface circuit is configured to output a second tracking signal based on one or more most significant bits of the digital envelope signal.

[0121] Aspect 18. An envelope tracking power source according to any one of Aspects 1 to 17, wherein the envelope tracking power source also includes a common-level element coupled to the input interface circuit, wherein the first output terminal of the input interface circuit is the first output terminal of the common-level element, and wherein the second output terminal of the input interface circuit is the second output terminal of the common-level element.

[0122] Aspect 19. An envelope tracking power source according to any one of Aspects 1 to 18, wherein the envelope tracking power source is coupled to a radio frequency (RF) front end (RFFE) transmit power amplifier, wherein the RFFE transmit power amplifier includes a voltage source input coupled to the output power port.

[0123] Aspect 20. An envelope tracking power source according to Aspect 19, wherein the output of the RFFE transmit power amplifier is coupled to an antenna.

[0124] Aspect 21. An envelope tracking power source according to any one of Aspects 18 to 20, wherein the output of the RFFE transmit power amplifier is coupled to the input of a power tracking coupler; wherein the output of the power tracking coupler is coupled to a feedback circuit, and the feedback circuit is configured to provide current supply feedback to the switching circuit.

[0125] Aspect 22. The envelope tracking power source of aspect 21, wherein the feedback circuit is part of a transceiver, and wherein the transceiver further comprises a digital to analog circuit having an output coupled to the envelope signal input port.

[0126] Aspect 23. An envelope tracking power source according to any one of Aspects 1 to 22, wherein the control input of the second amplifier is coupled to a modem circuit, and the modem circuit is configured to provide envelope tracking control data to the second amplifier.

[0127] Aspect 24. The envelope tracking power source of Aspect 23, wherein the first amplifier further comprises a control input, and wherein the modem circuit is coupled to the control input of the first amplifier.

[0128] Aspect 25. A method, the method comprising: calculating envelope information for a transmit signal by a control circuit of a modem; generating the transmit signal by a radio frequency front end (RFFE); providing a voltage to a power amplifier of the RFFE through an envelope tracking power source, wherein the envelope tracking power source comprises: an envelope signal input port, the envelope signal input port being configured to receive an envelope tracking signal generated according to the envelope information; an output power port, the output power port being configured to provide the voltage to the power amplifier; a first amplifier, the first amplifier having an input terminal and an output terminal; a second amplifier, the second amplifier having an input terminal, an output terminal and a control input terminal, wherein the control input terminal of the second amplifier is configured to program the second amplifier based on a current operating mode selected from a plurality of operating modes; an input interface circuit, The input interface circuit has an input coupled to the envelope signal input port, a first output coupled to the input of the first amplifier, and a second output coupled to the input of the second amplifier; a sensing and conditioning circuit having an output and one or more inputs coupled to the output of the first amplifier and the output of the second amplifier; a switching circuit having an input and an output, wherein the input is coupled to the output of the sensing and conditioning circuit, and wherein the output is coupled to the output power port; and an output filter circuit, wherein the output of the first amplifier is coupled to the output power port via the output filter circuit, and wherein the output of the second amplifier is coupled to the output power port via the output filter circuit.

[0129] Aspect 26. A method according to Aspect 25, wherein providing the voltage to the power amplifier includes programming the second amplifier with a control input signal at the control input terminal, wherein the control input signal is based on the current operating mode, a radio access technology (RAT) configuration, a peak-to-average power ratio of a radio frequency (RF) signal, or a bandwidth of the RF signal.

[0130] Aspect 27. A wireless communication device, comprising: a component for calculating envelope information for a transmission signal; a component for generating the transmission signal; and a component for providing an envelope tracking voltage to power a power amplifier that amplifies the transmission signal.

[0131] Aspect 28: A device comprising components for performing the operations according to any one of Aspects 1 to 26 above.

[0132] Aspect 29: A non-transitory computer-readable storage medium, comprising instructions stored thereon, which, when executed by one or more processors, enable the one or more processors to implement the operations described in any one of Aspects 1 to 26 above.

Claims

1. An envelope tracking power source, the envelope tracking power source comprising: Envelope signal input port; Output power port; a first amplifier having an input and an output; a second amplifier having an input, an output, and a control input, wherein the control input of the second amplifier is configured to set a power state for the second amplifier; an input interface circuit having an input coupled to the envelope signal input port, a first output coupled to the input of the first amplifier, and a second output coupled to the input of the second amplifier; a sensing and conditioning circuit having an output and one or more inputs coupled to the output of the first amplifier and the output of the second amplifier; a switching circuit having an input and an output, wherein the input is coupled to the output of the sensing and conditioning circuit, and wherein the output is coupled to the output power port; and An output filter circuit, wherein the output of the first amplifier is coupled to the output power port via the output filter circuit, and wherein the output of the second amplifier is coupled to the output power port via the output filter circuit. 2 . The envelope tracking power source of claim 1 , wherein the first amplifier is a main amplifier configured to provide linear amplification.

3. The envelope tracking power source of claim 1, wherein the control input is configured to set the power state for the second amplifier by switching the second amplifier between an on state and an off state.

4. The envelope tracking power source of claim 3, wherein the second amplifier is a peaking amplifier. 5 . The envelope tracking power source of claim 4 , wherein the second amplifier is configured to operate in a saturation mode during the on-state.

6. The envelope tracking power source of claim 1, wherein the control input is configured to set the power state based on a current operating mode selected from a plurality of operating modes.

7. The envelope tracking power source of claim 6, wherein the plurality of operating modes include a high power mode and a low power mode.

8. The envelope tracking power source of claim 6, wherein the control input is further based on one or more of a radio access technology (RAT) configuration, a peak-to-average power ratio of a radio frequency (RF) signal, and a bandwidth of the RF signal.

9. The envelope tracking power source of claim 1, further comprising a feedback circuit coupled between the sensing and conditioning circuit and the control input of the second amplifier, wherein the feedback circuit provides a feedback signal from the sensing and conditioning circuit to the control input to adjust a match between a power demand of a power amplifier coupled to the output power port and a voltage provided by the switching circuit, the first amplifier, and the second amplifier at the output power port.

10. The envelope tracking power source according to claim 1, further comprising: a first sensing element coupled between the output of the first amplifier and the input of the sensing and conditioning circuit; and A second sensing element is coupled between the output of the second amplifier and a second input of the sensing and conditioning circuit.

11. The envelope tracking power source according to claim 1, further comprising: a first sensing element coupled between the output of the first amplifier and the input of the sensing and conditioning circuit; and A second sensing element is coupled between the output of the second amplifier and a second input of the sensing and conditioning circuit.

12. The envelope tracking power source according to claim 1, further comprising: A sensing element having an input and an output, wherein the input is coupled to the output of the first amplifier and the output of the second amplifier, and wherein the output is coupled to the input of the sensing and conditioning circuit.

13. The envelope tracking power source of claim 1, wherein the output filter circuit comprises a first filter circuit coupled between the output terminal of the first amplifier and the output power port; The output filter circuit further includes a second filter circuit different from the first filter circuit, wherein the second filter circuit is coupled between the output terminal of the second amplifier and the output power port.

14. The envelope tracking power source of claim 1, wherein the first amplifier is a class AB amplifier, and wherein the second amplifier is a class C amplifier.

15. The envelope tracking power source of claim 1, wherein the first amplifier is a linear amplifier.

16. The envelope tracking power source of claim 15, wherein the second amplifier is a switching amplifier.

17. The envelope tracking power source of claim 1, wherein the input interface circuit is configured to receive a digital envelope signal at the envelope signal input port; wherein the input interface circuit is configured to output a first tracking signal at the first output terminal based on a set of least significant bits of the digital envelope signal; as well as And wherein the input interface circuit is configured to output a second tracking signal based on one or more most significant bits of the digital envelope signal.

18. The envelope tracking power source of claim 1, further comprising a common-stage element coupled to the input interface circuit, wherein the first output terminal of the input interface circuit is a first output terminal of the common-stage element, and wherein the second output terminal of the input interface circuit is a second output terminal of the common-stage element.

19. An envelope tracking power source according to claim 1, wherein the envelope tracking power source is coupled to a radio frequency (RF) front end (RFFE) transmit power amplifier, wherein the RFFE transmit power amplifier includes a voltage source input terminal coupled to the output power port.

20. The envelope tracking power source of claim 19, wherein an output of the RFFE transmit power amplifier is coupled to an antenna.

21. The envelope tracking power source of claim 19, wherein an output of the RFFE transmit power amplifier is coupled to an input of a power tracking coupler; The output terminal of the power tracking coupler is coupled to a feedback circuit, and the feedback circuit is configured to provide current supply feedback to the switching circuit.

22. The envelope tracking power source of claim 21, wherein the feedback circuit is part of a transceiver, and wherein the transceiver further comprises a digital to analog circuit having an output coupled to the envelope signal input port.

23. The envelope tracking power source of claim 21, wherein the control input of the second amplifier is coupled to a modem circuit, the modem circuit being configured to provide envelope tracking control data to the second amplifier.

24. The envelope tracking power source of claim 23, wherein the first amplifier further comprises a control input, and wherein the modem circuit is coupled to the control input of the first amplifier.

25. A method comprising: calculating, by a control circuit of the modem, envelope information for the transmitted signal; The transmit signal is generated by a radio frequency front end (RFFE); A voltage is provided to a power amplifier of the RFFE by an envelope tracking power source, wherein the envelope tracking power source comprises: An envelope signal input port, the envelope signal input port being configured to receive an envelope tracking signal generated according to the envelope information; an output power port configured to provide the voltage to the power amplifier; a first amplifier having an input and an output; a second amplifier having an input, an output, and a control input, wherein the control input of the second amplifier is configured to program the second amplifier based on a current operating mode selected from a plurality of operating modes; an input interface circuit having an input coupled to the envelope signal input port, a first output coupled to the input of the first amplifier, and a second output coupled to the input of the second amplifier; a sensing and conditioning circuit having an output and one or more inputs coupled to the output of the first amplifier and the output of the second amplifier; a switching circuit having an input and an output, wherein the input is coupled to the output of the sensing and conditioning circuit, and wherein the output is coupled to the output power port; and An output filter circuit, wherein the output of the first amplifier is coupled to the output power port via the output filter circuit, and wherein the output of the second amplifier is coupled to the output power port via the output filter circuit.

26. The method of claim 25, wherein providing the voltage to the power amplifier comprises programming the second amplifier at the control input with a control input signal, wherein the control input signal is based on the current operating mode, a radio access technology (RAT) configuration, a peak-to-average power ratio of a radio frequency (RF) signal, or a bandwidth of the RF signal.

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