CN210041760U

CN210041760U - Feedback-based power supply for radio frequency power amplifier

Info

Publication number: CN210041760U
Application number: CN201920777177.0U
Authority: CN
Inventors: 夏勤
Original assignee: Shaanxi Yacheng Microelectronics Co Ltd
Current assignee: Shaanxi Yacheng Microelectronics Co Ltd
Priority date: 2019-05-27
Filing date: 2019-05-27
Publication date: 2020-02-07
Anticipated expiration: 2029-05-27

Abstract

A feedback-based power supply for a radio frequency power amplifier, comprising: the power supply comprises a linear amplification unit, a first control unit, a first driving unit, a first feedback unit and a superposition unit, wherein the first control unit obtains a feedback signal of the change rate of an electric signal at a supply voltage end of the radio frequency power amplifier through the first feedback unit and outputs a first control signal so that the power supply works in any one of the following modes: a constant on time control mode with a constant on time, a constant off time control mode with a constant off time; the first driving unit is used for being connected with the output end of the first control unit and providing a first electric signal based on a first control signal; and the superposition unit is used for superposing the linearly amplified envelope signal and the first electric signal so as to supply power to a supply voltage end of the radio frequency power amplifier. The power output proportion of the switching power supply part can be improved, and therefore the efficiency of the power supply is improved.

Description

Feedback-based power supply for radio frequency power amplifier

Technical Field

The present disclosure relates to the field of mobile communications, and more particularly, to a feedback-based power supply for a radio frequency power amplifier.

Background

In the field of mobile communication, in order to improve the efficiency of the rf power amplifier, a hybrid power supply of a linear amplification unit combined with a switching power supply, which mostly adopts hysteretic control, may be used.

Although the technology is continuously developed, how to further improve the power supply efficiency of the rf power amplifier is always a technical problem to be considered in the art.

SUMMERY OF THE UTILITY MODEL

To solve the above technical problem, the present disclosure provides a feedback-based power supply for a radio frequency power amplifier, including:

a linear amplification unit, a first control unit, a first drive unit, and a first feedback unit and a superposition unit, wherein,

a linear amplification unit for linearly amplifying the first envelope signal and outputting a linearly amplified envelope signal;

the first control unit comprises a first input end which is used for accessing the linear amplified envelope signal;

the first control unit further comprises a second input end, and the second input end is used for obtaining a feedback signal of the change rate of the electric signal of the supply voltage end of the radio frequency power amplifier through the first feedback unit;

the first control unit further comprises an output, wherein: the first control unit outputs a first control signal based on the input of the first input end and the second input end so that the power supply works in any one of the following modes: a constant on time control mode with a constant on time, a constant off time control mode with a constant off time;

the first driving unit is used for being connected with the output end of the first control unit and providing a first electric signal based on the first control signal; and

and the superposition unit is used for superposing the linearly amplified envelope signal and the first electric signal so as to supply power to a supply voltage end of the radio frequency power amplifier.

Preferably, the first envelope signal is an envelope signal input to the radio frequency power amplifier.

Preferably, the rate of change of the electrical signal at the supply voltage terminal includes any one of or any combination of the following: the rate of change of voltage, the rate of change of current, the rate of change of envelope magnitude.

Preferably, the first driving unit includes a first switching amplifier, or includes: an upper power tube and a lower power tube.

Preferably, the power supply further includes a first mode selection unit for selecting between the constant on-time control mode and the constant off-time control mode.

Preferably, the first control unit comprises a timing unit for determining the constant on-time or constant off-time.

Preferably, the first and second liquid crystal materials are,

when the value of the first electric signal is lower than the first threshold value, the first control unit is further configured to force the power supply to continuously provide the first electric signal in the constant on-time control mode or the constant off-time control mode so that the value of the first electric signal is greater than or equal to the first threshold value.

Preferably, the first driving unit at least comprises a first switching amplifier and a second switching amplifier which are connected in parallel, and the first control unit is further configured to enable the first switching amplifier and the second switching amplifier to operate in a constant on-time control mode or a constant off-time control mode according to a time sequence.

Preferably, the constant on-time or constant off-time of at least one switching amplifier is different from that of the other switching amplifiers.

Preferably, the first and second liquid crystal materials are,

when the value of the electric signal in the branch to which any one of the parallel switching amplifiers belongs is lower than the threshold of the branch, the first control unit is further configured to force the power supply to continuously provide the electric signal in the branch to which the any one of the switching amplifiers belongs in a constant on-time control mode or a constant off-time control mode, and enable the value of the electric signal in the branch to be greater than or equal to the threshold of the branch; or

When the values of the electrical signals in the branches to which all the switching amplifiers connected in parallel belong are added to serve as the value of the first electrical signal, if the value of the first electrical signal is lower than the first threshold, the first control unit is further configured to force the power supply to continuously provide the first electrical signal in the constant on-time control mode or the constant off-time control mode so that the value of the first electrical signal is greater than or equal to the first threshold.

Through the technical scheme, the power supply for the radio frequency power amplifier is novel, and the first driving unit can be controlled to work in a constant on-time mode or a constant off-time mode based on the change rate of the electric signal of the supply voltage end outside the linear amplification unit. This helps to improve the utilization of the first drive unit and the overall efficiency of the power supply.

Drawings

FIG. 1 is a schematic diagram of a power supply configuration shown in one embodiment of the present disclosure;

FIG. 2A is a schematic diagram of a first drive unit of the power supply shown in one embodiment of the present disclosure;

FIG. 2B is a schematic diagram of a first drive unit of the power supply shown in one embodiment of the present disclosure;

FIG. 2C is a schematic diagram of a power supply according to one embodiment of the present disclosure;

FIG. 2D is a timing diagram illustrating one embodiment of the present disclosure;

FIG. 2E is a schematic diagram of a power supply according to one embodiment of the present disclosure;

fig. 3A (1) is a simulation diagram of a conventional hysteretic control power supply for which a first envelope signal is a 100MHz signal, and fig. 3B (1) is a waveform of a driving unit switch corresponding to a switching power supply portion of the conventional hysteretic control power supply;

fig. 3A (2) is a simulation diagram of a power supply in an embodiment of the present disclosure for a same first envelope signal being a 100MHz signal, and fig. 3B (2) is a waveform of a first driving unit switch corresponding to a switching power supply portion of the power supply;

FIG. 3C (1) illustrates a comparison of the switching frequency distribution of the aforementioned conventional hysteretic control power supply and the power supply of the embodiment of the present disclosure;

fig. 3C (2) illustrates a comparison of the time distribution of the switch conduction of the conventional hysteretic control power supply and the power supply of the embodiment of the present disclosure;

figure 3D (1) illustrates a simulation of the power of various parts of the conventional hysteretic control power supply during operation,

FIG. 3D (2) illustrates a simulation of power of various parts of the power supply of the embodiment of the present disclosure during operation;

FIG. 3E (1) illustrates a comparison of output power versus frequency curves for a conventional hysteretic control power supply and the power supply of the embodiments of the present disclosure at lower frequency ranges in the 0-100MHz range;

fig. 3E (2) illustrates a comparison of output power versus frequency curves for a conventional hysteretic control power supply and the power supply of the described embodiment of the present disclosure at lower frequencies in the frequency range of 0-25 MHz.

Detailed Description

In the following description, numerous details are set forth to provide a more thorough explanation of embodiments of the present disclosure. It will be apparent, however, to one skilled in the art that embodiments of the invention may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form, rather than in detail, in order to avoid obscuring embodiments of the present disclosure. Furthermore, features of different embodiments described below may be combined with each other, unless specifically stated otherwise.

The terms "first," "second," and the like as used in this disclosure are used for distinguishing between different objects and not for describing a particular order. Furthermore, "include" and "have," as well as any variations thereof, are intended to cover and not to exclude inclusions. For example, a process, method, system, or article or apparatus that comprises a list of steps or elements is not limited to only those steps or elements but may alternatively include other steps or elements not expressly listed or inherent to such process, method, system, article, or apparatus.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the disclosure, and the embodiment described is a portion of but not all embodiments of the disclosure. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It will be appreciated by those skilled in the art that the embodiments described herein may be combined with other embodiments.

Referring to fig. 1, in one embodiment, the present disclosure proposes a feedback-based power supply for a radio frequency power amplifier, comprising:

For the described embodiment the supply voltage of the radio frequency power amplifier is provided by superimposing the linearly amplified envelope signal and the first electrical signal, which is in contrast to the prior art, in which the supply voltage of the radio frequency power amplifier is provided to the radio frequency power amplifier by a single voltage or by two currents in parallel. The linearly amplified envelope signal and the first electrical signal are both related to the first envelope signal, and thus the above-described embodiments enable a new type of power supply for envelope tracking. It can be understood that the feedback-based power supply for the rf power amplifier is generated on the basis of the linear amplifying unit, the first control unit, the first feedback unit, the first driving unit, and the superimposing unit in the presence of the first envelope signal.

It is to be understood that the first control unit may be any COT control unit capable of implementing COT control. As for COT, two kinds are included: constant On Time, i.e., Constant On Time; and a Constant off time, Constant OffTime. It should be noted that the present disclosure does not focus on the innovative implementation of the COT control unit, and therefore, various COT control units in the prior art can be referred to, including a timer or a timer that may be involved in COT control, or other circuits or functional units cooperating with the timer or the timer, and the purpose of the present disclosure is mainly to calculate and determine a corresponding constant on-time or constant off-time.

That is, the above embodiment is also obviously different from the conventional power supply including a filtering unit and performing hysteresis control after filtering, and because the above embodiment does not need to use the filtering unit and hysteresis control but uses COT control, the frequency of the first driving unit is not limited by the circuit parameter L, the equivalent load, the hysteresis, the loop delay, the input signal, etc., and the first control unit can easily perform fast response and adjustment on the on-time or the off-time of the first driving unit, thereby improving the efficiency. That is, compared with the prior art adopting filtering and post-filtering hysteresis control, the embodiment has the advantages of simple scheme, high efficiency, capability of eliminating the jitter of the control signal and capability of reducing noise; moreover, the COT control response speed is high, and the method is very suitable for application scenes such as envelope tracking which require large input signal bandwidth and are convenient to expand.

More particularly, it is to be noted that: when the power supply works in the constant on-time mode or the constant off-time mode by controlling the first driving unit, the first driving unit enables the power supply to have the characteristics of the switching power supply, and the power supply comprises the linear amplifying unit, so the power supply is a hybrid envelope tracking power supply combining the characteristics of the linear amplifying unit and the switching power supply. However, with the rapid development of wireless communication technology, the 5G commercial era is about to start, and the 6G technology has also entered into research phase, and in the face of the rapid increase of various service data such as mobile internet, the power peak-to-average ratio (PAPR) of the rf input signal is getting larger, which results in the low efficiency of the linear amplification unit of constant voltage power supply under the condition of larger PAPR.

The above embodiments obviously help to solve the problem that the linear amplification unit has low efficiency under a large PAPR and thus reduces the efficiency of the whole power supply, because the above embodiments, besides the linear amplification unit, further control the first driving unit based on the change rate of the electrical signal at the supply voltage end to make the power supply operate in the constant on-time mode or the constant off-time mode, which helps to increase the duty ratio of the switching power supply in the whole power supply and reduce the duty ratio of the linear amplification unit according to the change rate of the electrical signal at the supply voltage end, thereby fully exerting the advantage of the high efficiency of the switching power supply. As such, the above-described embodiments contribute to further improving the efficiency of the overall power supply.

Furthermore, since the above-described embodiment further causes the power supply to operate in the constant on-time mode or the constant off-time mode by controlling the first driving unit based on the rate of change of the electric signal supplied to the voltage terminal in addition to the linear amplification unit, it further causes: the first driving unit in the power supply enables the power supply to externally show the characteristic of a switching power supply, and the on and off of the switching power supply are not influenced by the bandwidth of an envelope signal but influenced by the change rate of an electric signal at the supply voltage end. This also shows that the power supply disclosed in the above embodiment has a higher anti-jamming capability, and helps to increase the duty ratio of the switching power supply during the whole power supply operation, thereby improving the efficiency of the whole power supply by utilizing the high efficiency characteristic of the switching power supply.

This is common knowledge in the field of circuits, as regards the matching of the time constants or delays of the individual circuits themselves. The disclosure does not focus on how to design and adjust the time constant, and therefore, the detailed description thereof is omitted.

It is understood that the signal in the above embodiments may be a current signal or a voltage signal. Hereinafter, the various electrical signals are similar to each other, and will not be described in detail hereinafter. Similarly, the power supply of the above embodiment may be an analog power supply, or may be a digital power supply, as long as the power supply can be implemented as an analog circuit or a digital circuit.

In addition, the above embodiment prefers the constant on-time mode when the rf power amplifier is judged to be lightly loaded or unloaded. This is because the constant on-time mode is more advantageous to reduce the switching loss and improve the power supply efficiency at light load or no load than the increase in the switching loss and the reduction in the power supply efficiency at light load caused by the constant off-time mode.

In addition, it should be noted that, regarding the functional implementation of the superimposing unit, if the power supply of the above embodiment is an analog power supply, then: (1) when the signal output by the first driving unit is a current signal, the circuits corresponding to the signal and the linearly amplified envelope signal can realize the superposition of the current in a parallel mode; (2) when the signal output by the first driving unit is a voltage signal, the voltage superposition can be realized by the circuits corresponding to the signal and the linearly amplified envelope signal respectively in a series connection mode; in addition, if the power supply of the above-described embodiment is a digital power supply, any digital circuit can be used to realize the present invention as long as the digital signal of the signal output by the first driving unit and the linearly amplified envelope signal can be superimposed by the digital circuit. For the various embodiments below, if reference is made to the above-described analog or digital power supply, this paragraph is analogous.

In another embodiment, the first envelope signal is an envelope signal input to the radio frequency power amplifier.

For the embodiment, when the first envelope signal is the envelope signal input to the radio frequency power amplifier, as in most of the prior art solutions, the embodiment uses the radio frequency (i.e. RF) input signal as the reference signal for envelope tracking, and the embodiment also uses the envelope signal input to the radio frequency power amplifier from the signal source to realize envelope tracking. However, this is not meant to exclude other first envelope signals from the present disclosure, and it will be apparent that the relevant embodiments are not limited to the source of the envelope signals in accordance with the principles disclosed in the present disclosure in order to achieve the technical effects of the various embodiments described above.

In another embodiment, the rate of change of the electrical signal at the supply voltage terminal includes any one of or any combination of the following: the rate of change of voltage, the rate of change of current, the rate of change of envelope magnitude.

For this embodiment, the rate of change of the voltage supplied to the voltage terminal is the derivative of the terminal voltage with respect to time; the rate of change of the current is the derivative of the current with respect to time; the rate of change of the envelope magnitude is the derivative of the envelope magnitude with respect to time. In the prior art, methods for detecting and processing the change rate of the voltage, the current and the envelope amplitude can be referred to, and are not limited herein, and the corresponding first feedback unit can be specifically implemented as: the device comprises a slew rate processing unit, a current slope or change rate processing unit and an envelope slew rate processing unit.

In the traditional hysteresis control power supply, a comparator is mostly adopted to compare the voltage value of the output end of the power supply with a set reference voltage to determine the conduction time point of a corresponding driving unit, so that the traditional hysteresis control power supply is sensitive to output noise and is easy to cause the misconduction of a switch. The sensitivity to noise and envelope signal bandwidth is reduced through the feedback of the signal change rate of the supply voltage end (also called a power supply input end) of the power amplifier, so that when the power supply works in a switching power supply, the conduction time point of the power supply is more accurately fixed at the optimal position, the switching frequency is limited within a certain range, the frequency jitter required by anti-electromagnetic interference (EMI) is realized, the linearity of a power supply system is not influenced, and the integral efficiency of the power supply is remarkably improved.

It will be appreciated that the rate of change of the voltage, the rate of change of the current, the rate of change of the envelope magnitude may be obtained by various sensing or sensing elements. Typically, the rate of change may be sensed by inductance or capacitance, or: the change rate of the voltage, the change rate of the current and the change rate of the envelope amplitude are obtained by a sensing element for acquiring the voltage or the current or the envelope amplitude at a high speed and a controller or a processor through further calculation. Preferably, a relatively sensitive inductor and/or capacitor is used to obtain any one or any combination of the following at low cost: the rate of change of the voltage, the rate of change of the current, the rate of change of the envelope magnitude.

In another embodiment, when the rate of change of the electrical signal at the supply voltage end is lower than a certain rate of change threshold, the first control unit is further configured to control the first driving unit to forcibly cause the power supply to operate in a constant on-time mode or a constant off-time mode.

It will be appreciated that this is to increase the duty cycle of the switching power supply as much as possible throughout the power supply, and that the rate of change threshold should be as low as possible whether the switching power supply is operating in a constant on-time mode or a constant off-time mode throughout the power supply. Meanwhile, it can be understood that, if there is no such change rate threshold, the foregoing embodiments may still enable the power supply to operate in the constant on-time mode or the constant off-time mode only according to the change rate of the electrical signal of the supply voltage terminal, for example, whether the first driving unit operates or not and the frequency thereof are controlled according to the specific value of the change rate of the electrical signal of the supply voltage terminal, so as to enable the power supply to operate in the constant on-time mode or the constant off-time mode.

Preferably, the rate of change threshold may be preset or even modifiable. Although theoretically, the change rate threshold should be as low as possible, in order to reduce the loss caused by frequent switching and optimize the efficiency of the whole power supply, the change rate threshold can be preset according to the differential signal of the maximum operating bandwidth (note: the bandwidth is known information and can be obtained in various ways) of the envelope signal to be processed, and can be changed and updated according to different envelope signals in different operating scenes.

Taking the rate of change of voltage as an example, in terms of envelope signals in current radio frequency communication technology, generally, the rate of change threshold may be selected from the following range: 900V/. mu.s-1800V/. mu.s.

Specifically, in each on/off period of the first driving unit, the voltage change rate SR of the supply voltage end of the radio frequency power amplifier_S4And when the change rate is larger than or equal to the change rate threshold, triggering an on-time timing module in the first control unit, and when the COT controls the constant on-time mode, starting timing by the constant on-time Ton, and starting the on-state of the first driving unit and turning off the first driving unit when the timing is finished. It can be appreciated that if the COT control is a constant off-time approach, the constant off-time Toff may further be provided with a minimum off-time for satisfying the duration required for circuit signal acquisition.

The on-time timing module is used for determining a constant on-time and/or a constant off-time, and may be any element, device, apparatus or circuit that can be used to implement a timing function in the prior art.

In another embodiment, the first driving unit includes a first switching amplifier, or includes: an upper power tube and a lower power tube.

It can be understood that the switching amplifier is obviously used to implement a driving unit of a switching power supply;

for this embodiment, referring to fig. 2A, take the example that the first driving unit includes an upper power transistor M1 and a lower power transistor M2:

as shown in fig. 2A, the first driving unit includes an upper power transistor M1 and a lower power transistor M2, wherein one terminal of M1 is connected to VDD power supply, one terminal of M2 is grounded, the common terminal of M1 and M2 is an output terminal, and the gates of M1 and M2 are respectively connected to the output terminal of the control unit, and are turned on or off based on the gate voltage provided by the first control unit.

Further, if the voltage change rate and the change rate threshold value are described in conjunction with the foregoing embodiment, in each period, when the voltage change rate of the supply voltage terminal of the rf power amplifier is greater than or equal to the change rate threshold value, the first control unit outputs a control signal to drive the upper power transistor M1 to be turned on (at this time, M2 is in an off state), and starts the on-time timing module to start timing; when the timing is finished, the first control unit outputs a control signal to drive the upper power tube M1 to be turned off and the upper power tube M2 to be turned on.

In another embodiment, the power supply further comprises a first mode selection unit for selecting between the constant on-time control mode and the constant off-time control mode.

For this embodiment, an implementation of the mode selection is given, i.e. the selection is made by the first mode selection unit. It is understood that the selection may be implemented by hardware circuitry, or by software calculations. In addition, whether by hardware circuit or software calculation, as described above, when the rf power amplifier is determined to be under light load or idle load, the constant on-time control mode may be further preferred.

As previously mentioned, in another embodiment, the first control unit comprises a timing unit for determining the constant on-time or constant off-time.

It should be noted that, as to how to determine the constant on-time or the constant off-time, all corresponding means in the prior art can be adopted, and this disclosure is not repeated herein.

In another embodiment of the present invention, the substrate is,

when the value of the first electric signal is lower than a first threshold value, the first control unit is further configured to force the power supply to continuously provide the first electric signal in a constant on-time control mode or a constant off-time control mode so as to achieve the following control objectives: the value of the first electric signal is equal to or greater than a first threshold value.

For this embodiment, the first threshold is to avoid to the greatest extent that may occur in some cases: a situation in which the power supply is not operating stably. Without the means associated with this first threshold, the power supply may still operate stably. That is, this embodiment is secondary, enhanced. This is because, in engineering, in some radio frequency systems, it may happen that, under a very low probability, the envelope signal changes smoothly and the change rate of the signal at the supply voltage end cannot be sensed by the sensing element in time, so that the first driving unit does not operate the power supply in the constant on-time control mode or the constant off-time control mode, that is, the characteristics of the switching power supply in the power supply are not presented to the outside. Therefore, it can be understood that the present embodiment is to make the first control unit forcibly start the COT control mode of the present power supply in this situation, so as to prevent the situation that the signal change of the supply voltage end is gradual and the COT control mode cannot be started, and improve the reliability of the whole power supply system in an extreme case.

It will be appreciated that the smaller the first threshold value, the better, e.g. the first threshold value is a value close to zero, preferably zero.

It should be noted that the value of the first electrical signal may be directly obtained inside the first driving unit and then output to the first control unit, or may be processed by the second feedback unit and then fed back to the first control unit (see the related paragraph of fig. 2C later in detail). It can be appreciated that at this point the first control unit may set the corresponding third input to access the value of the first electrical signal.

In another embodiment, the first driving unit includes a first switching amplifier and a first inductor.

It can be appreciated that the switching amplifier is suitable for higher frequency applications, particularly GaN switching amplifiers. And the current in the branch circuit is stored and released through the corresponding first inductor. In addition, a capacitor may be further included as an energy storage device, if necessary.

In another embodiment, as shown in fig. 2B, the first driving unit includes at least a first switching amplifier and a second switching amplifier connected in parallel, and the first control unit is further configured to operate the first switching amplifier and the second switching amplifier in a constant on-time control mode or a constant off-time control mode according to a timing sequence.

It can be appreciated that the above-described embodiments enable multi-phase control since a plurality of switching amplifiers are controlled in time series.

Furthermore, referring to the previous embodiment, in the embodiment shown in fig. 2B, each switching amplifier belongs to a branch, which may include a corresponding inductor.

As previously mentioned, in another embodiment,

the first switching amplifier and the second switching amplifier are selected from any one of the following: a GaN switching amplifier, a Si-based switching amplifier. It is clear that this embodiment is for higher frequency signals, since the switching frequency of GaN switching amplifiers can reach very high levels. Similarly, a Si-based switching amplifier (i.e., a silicon-based switching amplifier, also referred to as a silicon-based switching amplifier) with a high switching frequency may also be used. It will be appreciated that the associated switching amplifier may have more options if it is not required for higher frequency signals. For the various embodiments of the present disclosure, the selection of the switching amplifier depends on the frequency range of the signal it processes.

Referring to fig. 2C, in another embodiment, an i-way switching amplifier is connected in parallel and then connected in series with an inductor, wherein,

LA denotes a linear amplification unit, for example, the linear amplification unit may select at least one of a class a or AB linear amplifier;

PA denotes a radio frequency power amplifier;

vout represents the voltage output terminal of the power supply, which is connected to the supply voltage terminal of the radio frequency power amplifier;

s1 denotes a first envelope signal, S2 denotes a linearly amplified envelope signal, S3 denotes a first electrical signal, S4 denotes a signal obtained by superimposing S2 and S3 (wherein the superimposing unit is not shown), S5 denotes a feedback signal of S4, S6 denotes a signal output to the first control unit by the first feedback unit, i.e., a signal at the second input terminal of the first control unit, S7 denotes a value of the first electrical signal, and S8 denotes a feedback signal reflecting the first electrical signal output to the first control unit via the second feedback unit;

the first control unit is connected with the i-path switching amplifier of the first driving unit; s7 can be led out from any end of the inductor L.

Further, taking i-3 as an example, see fig. 2D,

as shown in fig. 2D, the first control unit provides a constant on or off time control signal to each switching amplifier according to a timing, each switching amplifier is turned on according to the timing, and outputs a driving signal. The first control unit outputs a control signal Vc1 with a constant on-time Ton to the first switching amplifier, a control signal Vc2 with a constant on-time Ton to the second switching amplifier, and a control signal Vc3 with a constant on-time Ton to the third switching amplifier. The control signal Vc2 is enabled at the falling edge of the on pulse of the control signal Vc1, and similarly, the control signal Vc3 is enabled at the falling edge of the on pulse of the control signal Vc 2. The control mode of conducting according to the time sequence enables the first driving unit to realize multi-phase control. It can be appreciated that the timing sequence shown in FIG. 2D is only one example; it can be understood that, at another timing, the control signal Vc1 is enabled at the timing of the falling edge of the on pulse of the control signal Vc2, and the control signal Vc3 is enabled at the timing of the falling edge of the on pulse of the control signal Vc 1.

It should be noted that the three-way Ton shown in fig. 2D may be the same or different.

It can be appreciated that for multiple parallel switching amplifiers, a constant on-time Ton that is not exactly the same can cope with the variability and complexity of the envelope signal. Further, the constant on-time or constant off-time may be dynamically adjusted. In this case, the constant on-time or the constant off-time of each path may be calculated according to the specific conditions of the first envelope signal or the signal output by the first feedback unit, the first electrical signal, and the signal at the supply voltage end, or by integrating the means of how to determine the constant on-time or the constant off-time in the prior art. It can be understood that when the first driving unit has only one switching amplifier, the constant on time or the constant off time may be determined by referring to the above calculation method.

As such, in another embodiment, the constant on-time or constant off-time of at least one switching amplifier may be different from that of the other switching amplifiers.

Referring to fig. 2E, in another embodiment, each of the i switching amplifiers is connected in series with a corresponding inductor and then connected in parallel to form the first driving unit, and at this time, S7 is led out from a common end of all the inductors connected in parallel.

In another embodiment of the present invention, the substrate is,

With regard to this embodiment, with reference to the foregoing embodiment regarding the first threshold, it can be understood that, when the first driving unit includes a plurality of switching amplifiers connected in parallel, in order to improve the stability to the greatest extent, the COT control mode may be ensured to be activated by a certain branch threshold in a corresponding branch or a corresponding first threshold after the values of the electrical signals in all branches are added.

The prior art is compared with the present disclosure below, in conjunction with the attached figures:

fig. 3A (1) is a simulation diagram of a conventional hysteretic control power supply for which a first envelope signal is a 100MHz signal, and fig. 3B (1) is a waveform of a driving unit switch corresponding to a switching power supply portion of the conventional hysteretic control power supply; wherein: the signal S3_1 represents the first electrical signal output by the driving unit, and the signal S1 represents the first envelope signal;

fig. 3A (2) is a simulation diagram of a power supply in an embodiment of the present disclosure for a same first envelope signal being a 100MHz signal, and fig. 3B (2) is a waveform of a first driving unit switch corresponding to a switching power supply portion of the power supply; wherein: signal S3 represents a first electrical signal according to embodiments of the present disclosure, and signal S1 represents the same first envelope signal as used by a conventional hysteretic control power supply;

referring to fig. 3A (1), 3B (1), 3A (2), and 3B (2), the ordinate represents the normalized current signal magnitude (unit: amp), the abscissa represents the signal sampling time (unit: 1nsec/per sample), and a comprehensive comparison of these 4 figures shows: the first electrical signal S3 output by the first driving unit corresponding to the switching power supply portion in the power supply disclosed by the present disclosure is significantly closer to the first envelope signal S1, which indicates that the power supply disclosed by the present disclosure optimizes the optimal on-time point of the switch in the COT control mode.

Furthermore, fig. 3C (1) illustrates a comparison of the switching frequency distribution of the aforementioned conventional hysteretic control power supply and the power supply of the embodiment of the present disclosure, wherein: the ordinate represents the normalized number of statistical distributions (unit: number), the abscissa represents the switching frequency (unit: 100MHz), SF1 represents the switching frequency distribution of a conventional hysteretic control power supply, SF2 represents the switching frequency distribution of the power supply of the embodiments of the present disclosure, and it can be seen from the comparison in the figure that: the power supply of the present disclosure can significantly reduce the average frequency of the switches; through simulation calculation, the average frequency of the switch is reduced from 50MHz to 35MHz by the embodiment.

Fig. 3C (2) illustrates a comparison of the time distribution of the switch conduction of the conventional hysteretic control power supply and the power supply of the embodiment of the present disclosure, wherein: the ordinate represents the normalized number (unit: number) of statistical distribution of the conduction time, the abscissa represents the conduction time (unit: 10nsec), Ton1 represents the time distribution of the switch conduction of the conventional hysteretic control power supply, Ton2 represents the time distribution of the switch conduction of the power supply of the embodiment of the present disclosure, and it can be seen from comparison in the figure that: the time distribution that this disclosed switch switched on is less than traditional hysteresis control power far away, and the time that this disclosed switch switched on can be fixed basically, has very strong interference killing feature, has promoted the control accuracy of COT control mode's the best time point that switches on. Through simulation calculation, the on time of the switch in the embodiment is about 8-9 ns.

Further, fig. 3D (1) illustrates a simulation of power of each part of the conventional hysteretic control power supply during operation, and fig. 3D (2) illustrates a simulation of power of each part of the power supply according to the embodiment of the present disclosure during operation, wherein: the ordinate represents the normalized power spectrum (unit: dBm/Hz), the abscissa represents the bandwidth (unit: MHz), P _ S1 represents the power of the first envelope signal, P _ L1_1 represents the power of the linear amplification unit in the conventional hysteretic control power supply, P _ S3_1 represents the power of the switching power supply section in the conventional hysteretic control power supply, P _ L1 represents the power of the linear amplification unit in the power supply of the present embodiment, P _ S3 represents the power of the switching power supply section in the power supply of the present embodiment, comparing fig. 3D (1) and fig. 3D (2), particularly, the circled portion in fig. 3D (1) and the low-frequency band region corresponding to the corresponding portion in fig. 3D (2), it can be seen that: in the traditional hysteresis control power supply, the power output ratio of a linear amplification unit is relatively high; the power supply of the embodiment improves the power ratio of the switching power supply part, and particularly has significant advantages over the conventional hysteretic control power supply in low-frequency power output, and most of the energy (considered as 99% of the energy) of the envelope of the radio frequency signal is concentrated below 20MHz, so that the power supply of the embodiment effectively inhibits the power output of the linear amplifier, and the efficiency of the whole power supply system is improved. Since the efficiency of the switching power supply is higher than that of the linear amplification unit, the power supply of the embodiment of the disclosure has significantly improved efficiency compared to the prior art.

Further, on the basis of fig. 3D (1) and fig. 3D (2), in terms of the low frequency band, fig. 3E (1) illustrates a comparison of output power variation curves with frequency of the conventional hysteretic control power supply and the power supply of the embodiment of the present disclosure in the range of 0-100MHz when the frequency range is lower, while fig. 3E (2) illustrates a comparison of output power variation curves with frequency of the conventional hysteretic control power supply and the power supply of the embodiment of the present disclosure in the range of 0-25MHz lower, as can be seen from the following diagrams:

the power curve P _ L1_1 of the linear amplifying unit in the traditional hysteretic control power supply is convex downward at about 2.5MHz in the low frequency band, which indicates that the linear amplifying unit outputs higher power and also brings larger loss, while the output power of the linear amplifying unit in the frequency range lower than 20MHz in the present disclosure is significantly lower than that of the linear amplifying unit in the hysteretic control power supply in the prior art, and most of the energy (which can be considered as 99% of the energy) of the envelope of the radio frequency signal is concentrated below 20MHz, which fully indicates that the excellent performance of the embodiment in the low frequency range of the present disclosure significantly improves the efficiency of the entire power supply.

Furthermore, in some embodiments, the control unit may be provided on a chip or processor (e.g., silicon) of the digital transmitter. Furthermore, the driving unit may also be provided on a chip or processor of the digital transmitter. More broadly, the remaining units may also be provided on the relevant chip or processor. The above power supply may naturally also be provided on the chip or processor of the digital transmitter.

Embodiments of the present invention may be implemented in hardware or in software, depending on the particular implementation requirements. The implementation may be performed using a digital storage medium (e.g., a floppy disk, DVD, blu-ray, CD, ROM, PROM, EPROM, EEPROM, or FLASH memory) having electronically readable control signals stored thereon. Accordingly, the digital storage medium may be computer-readable.

In some embodiments, a programmable logic device (e.g., a field programmable gate array) may be used to perform some or all of the functions of the methods described herein. In some embodiments, a field programmable gate array may cooperate with a microprocessor to implement the power supplies described herein.

The above-described embodiments are merely illustrative of the principles of the present disclosure. It is to be understood that modifications and variations of the arrangements and details described herein will be apparent to those skilled in the art. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto, and not by the specific details presented by way of the description and illustration of the embodiments presented herein.

Claims

1. A feedback-based power supply for a radio frequency power amplifier, comprising:

2. The power supply of claim 1, wherein the first envelope signal is an envelope signal input to the radio frequency power amplifier.

3. The power supply of claim 1, wherein the rate of change of the electrical signal at the supply voltage terminal comprises any one or any combination of: the rate of change of voltage, the rate of change of current, the rate of change of envelope magnitude.

4. The power supply of claim 1, wherein the first driving unit comprises a first switching amplifier, or comprises: an upper power tube and a lower power tube.

5. The power supply of claim 1, wherein the power supply further comprises a first mode selection unit for selecting between the constant on-time control mode and a constant off-time control mode.

6. The power supply of claim 1, wherein the first control unit comprises a timing unit for determining the constant on-time or constant off-time.

7. The power supply of claim 1, wherein,

8. The power supply of claim 1, wherein the first driving unit comprises at least a first switching amplifier and a second switching amplifier connected in parallel, and the first control unit is further configured to operate the first switching amplifier and the second switching amplifier in a constant on-time control mode or a constant off-time control mode according to a timing sequence.

9. The power supply of claim 8, wherein the constant on time or constant off time of at least one switching amplifier is different from that of the other switching amplifiers.

10. The power supply of claim 8,

When the values of the electrical signals in the branches to which all the switching amplifiers connected in parallel belong are added to serve as the value of the first electrical signal, if the value of the first electrical signal is lower than a first threshold, the first control unit is further configured to force the power supply to continuously provide the first electrical signal in a constant on-time control mode or a constant off-time control mode so that the value of the first electrical signal is greater than or equal to the first threshold.