Radio frequency switch power supply circuit

Abstract

The embodiment of the invention provides a radio frequency switch power supply circuit. The radio frequency switch power supply circuit comprises a signal generation module and a multi-stage charge pump circuit, the signal generation module is used for sending a first square wave signal to the multi-stage charge pump circuit in the channel switching process of the radio frequency switch and sending a second square wave signal to the multi-stage charge pump circuit after the radio frequency switch completes channel switching, and the frequency of the first square wave signal is larger than that of the second square wave signal; and the multi-stage charge pump circuit is used for boosting the input voltage according to the signal sent by the signal generation module so as to supply power to the radio frequency switch. According to the invention, the signal generation module sends the first square wave signal with high frequency to the multi-stage charge pump circuit in the channel switching process of the radio frequency switch, and sends the second square wave signal with low frequency to the multi-stage charge pump circuit after the radio frequency switch completes the channel switching, so that the radio frequency switch can complete the rapid channel switching. And the noise generated after the channel switching is completed is relatively low.

Description

Technical Field

[0001] The present application relates to the technical field of integrated circuits, and in particular to a radio frequency switch power supply circuit. Background Art

[0002] One of the key indicators of RF switches is the ability to support low DC power supply voltage VDD. In the evolution of communication systems, the supply voltage VDD of the DC power port of RF front-end chips tends to be gradually reduced, but the key RF N-type field effect MOS tube in the RF switch requires a higher bias voltage (VBIAS) to ensure RF performance.

[0003] At present, in order to ensure RF performance, the charge pump boost architecture is mainly used. The lower the voltage value of the power supply voltage VDD, the higher the number of charge pump stages is set accordingly. The step-by-step boost ensures that the RF N-type field effect MOS tube in the RF switch can obtain a sufficiently high voltage.

[0004] However, as the number of charge pump stages increases, the number and single capacitance value of the flying capacitors (Flying Cap) of the charge pump will increase, and the driving capability of the flying capacitor driver tube will need to be increased accordingly, resulting in an increase in the size of the flying capacitor driver tube, which in turn causes the edge of the flying capacitor voltage square wave to become steeper, indirectly increasing the RF noise. Summary of the invention

[0005] In view of this, an embodiment of the present application provides a radio frequency switch power supply circuit to at least partially solve the above-mentioned problem.

[0006] According to a first aspect of an embodiment of the present application, a radio frequency switch power supply circuit is provided, comprising: a signal generating module and a multi-stage charge pump circuit; the signal generating module is used to send a first square wave signal to the multi-stage charge pump circuit during channel switching of the radio frequency switch, and send a second square wave signal to the multi-stage charge pump circuit after the radio frequency switch completes channel switching, wherein the frequency of the first square wave signal is greater than the frequency of the second square wave signal; the multi-stage charge pump circuit is used to boost an input voltage according to a signal sent by the signal generating module to power the radio frequency switch.

[0007] In a possible implementation, the signal generating module includes: an enable signal generating module and a square wave oscillator; the enable signal generating module is used to generate a first enable signal in response to a channel switching start signal of the radio frequency switch, and to generate a second enable signal in response to a channel switching end signal of the radio frequency switch; the square wave oscillator is used to generate the first square wave signal according to the first enable signal when the enable signal generating module generates the first enable signal, and to generate the second square wave signal according to the second enable signal when the enable signal generating module generates the second enable signal.

[0008] In a possible implementation, the multi-stage charge pump circuit includes: an inverter and at least two charge pumps connected in series; the charge pump includes: two drivers, two flying capacitors, a control switch and an output capacitor, the two drivers include a first driver and a second driver, and the two flying capacitors include a first flying capacitor and a second flying capacitor; the output end of the first driver is electrically connected to the first end of the first flying capacitor, and the output end of the second driver is electrically connected to the first end of the second flying capacitor; the control switch is electrically connected to the second end of the first flying capacitor and the second end of the second flying capacitor respectively; the first end of the output capacitor is electrically connected to the control switch, and the second end of the output capacitor is grounded; the first end of the output capacitor in the non-final charge pump of the at least two charge pumps is electrically connected to the control switch, and the second end of the output capacitor is grounded; One end is electrically connected to the control switch in the next-stage charge pump, and the first end of the output capacitor in the final-stage charge pump of the at least two charge pumps is electrically connected to the RF switch; the control end of the first driver is electrically connected to the output end of the square wave oscillator, the input end of the inverter is electrically connected to the output end of the square wave oscillator, and the output end of the inverter is electrically connected to the control end of each of the second drivers; the first driver is used to charge the connected first flying capacitor according to the square wave signal output by the square wave oscillator; the second driver is used to charge the connected second flying capacitor according to the square wave signal output by the inverter; the control switch is used to control the charging and discharging of the two flying capacitors, wherein the output capacitor is charged when the two flying capacitors are discharged.

[0009] In a possible implementation manner, a capacitance value of an output capacitor in a non-final-stage charge pump among the at least two charge pumps is smaller than a capacitance value of an output capacitor in a final-stage charge pump among the at least two charge pumps.

[0010] In a possible implementation, the control switch includes: a first MOS tube, a second MOS tube, a third MOS tube and a fourth MOS tube; the output end of the first MOS tube, the input end of the third MOS tube, the control end of the second MOS tube, and the control end of the fourth MOS tube are electrically connected to the second end of the first flying capacitor, the input end of the first MOS tube is electrically connected to the input end of the second MOS tube and is grounded, the control end of the first MOS tube, the output end of the second MOS tube, the control end of the third MOS tube, and the input end of the fourth MOS tube are electrically connected to the second end of the second flying capacitor, and the output ends of the third MOS tube and the fourth MOS tube are electrically connected to the first end of the output capacitor.

[0011] In a possible implementation, the driver includes: a main drive inverter, at least one auxiliary drive inverter, two analog switches and a power supply, wherein the two analog switches include a first analog switch and a second analog switch; the driving end of the main drive inverter is electrically connected to the output end of the square wave oscillator, the input end of the main drive inverter is electrically connected to the first end of the power supply, and the other end of the power supply is connected to the ground; the input end of the main drive inverter and the input end of the auxiliary drive inverter are electrically connected to the first end and the second end of the first analog switch, respectively, and the ground end of the main drive inverter and the ground end of the auxiliary drive inverter are electrically connected to the ground end of the auxiliary drive inverter, respectively. The first end and the second end of the second analog switch are electrically connected, the driving end of the auxiliary drive inverter is electrically connected to the output end of the square wave oscillator or the output end of the inverter, the output end of the auxiliary drive inverter is electrically connected to the first end of the first flying capacitor or the second flying capacitor, and the control end of the analog switch is electrically connected to the output end of the enable signal generating module; the analog switch is used to close when receiving the first enable signal to electrically connect the auxiliary drive inverter to the main drive inverter, and to open when receiving the second enable signal to disconnect the auxiliary drive inverter from the main drive inverter.

[0012] In a possible implementation, the main drive inverter includes: a fifth MOS tube and a sixth MOS tube, the auxiliary drive inverter includes: a seventh MOS tube and an eighth MOS tube, the first analog switch includes: a ninth MOS tube, and the second analog switch includes a tenth MOS tube; the control end of the fifth MOS tube, the control end of the sixth MOS tube, the control end of the seventh MOS tube, and the control end of the eighth MOS tube are electrically connected to the output end of the square wave oscillator; the input end of the fifth MOS tube is electrically connected to the first end of the power supply and the input end of the ninth MOS tube, the other end of the power supply is grounded, the output end of the fifth MOS tube, the output end of the sixth MOS tube, the output end of the seventh MOS tube, and the output end of the eighth MOS tube are electrically connected to the first end of the first flying capacitor or the second flying capacitor; the input end of the sixth MOS tube is electrically connected to the input end of the tenth MOS tube and is grounded; the control ends of the ninth MOS tube and the tenth MOS tube are electrically connected to the output end of the enable signal generating module; the output end of the ninth MOS tube is electrically connected to the input end of the seventh MOS tube, and the output end of the tenth MOS tube is electrically connected to the input end of the eighth MOS tube.

[0013] In a possible implementation, a ratio interval of the frequency of the first square wave signal to the frequency of the second square wave signal is [3, 12].

[0014] In a possible implementation manner, a frequency interval of the second square wave signal is [1 MHz, 5 MHz].

[0015] In a possible implementation, the capacitance value interval of the output capacitor in the non-final charge pump among the at least two charge pumps is [1pF, 4pF], and the capacitance value of the output capacitor in the final charge pump among the at least two charge pumps is greater than or equal to 40pF.

[0016] In a possible implementation manner, the capacitance values ​​of the first flying capacitor and the second flying capacitor are greater than or equal to 8 pF.

[0017] It can be seen from the above technical solution that, by sending a first square wave signal with a higher frequency to the multi-stage charge pump circuit through the signal generation module during the channel switching process of the RF switch, and sending a second square wave signal with a lower frequency to the multi-stage charge pump circuit after the RF switch completes the channel switching, the RF switch can complete fast channel switching, and the noise generated after the channel switching is completed is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0019] Figure 1 is a schematic diagram of a radio frequency switch power supply circuit provided in an embodiment of the present application;

[0020] Figure 2 It is a schematic diagram of the interstage circuit of a 3-stage full-cycle 8-tube charge pump circuit;

[0021] Figure 3 It is a schematic diagram of a single-stage, full-cycle 8-tube charge pump;

[0022] Figure 4 is a schematic diagram of a radio frequency switch power supply circuit including an inverter provided in an embodiment of the present application;

[0023] Figure 5 is a circuit diagram of a radio frequency switch power supply circuit provided in an embodiment of the present application;

[0024] Figure 6 It is a schematic diagram of a radio frequency switch power supply circuit including a main drive inverter provided in an embodiment of the present application. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the embodiments of the present application should fall within the scope of protection of the embodiments of the present application.

[0026] The terms used in this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used in this article refers to and includes any or all possible combinations of one or more associated listed items.

[0027] It should be understood that although the terms first, second, third, etc. may be used in the present application to describe various information, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0028] Figure 1 is a schematic diagram of a radio frequency switch power supply circuit provided in an embodiment of the present application, such as Figure 1 As shown, the RF switch power supply circuit 100 includes: a signal generating module 101 and a multi-stage charge pump circuit 102 .

[0029] The signal generating module 101 is used to send a first square wave signal to the multi-stage charge pump circuit 102 during the channel switching of the RF switch, and send a second square wave signal to the multi-stage charge pump circuit after the RF switch completes the channel switching, wherein the frequency of the first square wave signal is greater than the frequency of the second square wave signal. The multi-stage charge pump circuit 102 is used to boost the input voltage according to the signal sent by the signal generating module 101 to power the RF switch 200.

[0030] The RF (RFSwitch) switch is a signal channel converter that can switch between multiple signal channels, and the RF switch can support low DC power supply voltage VDD. In the upgrade and evolution of communication systems, the power supply voltage VDD of the DC power supply port of the RF switch front-end chip has a tendency to gradually decrease. The VDD of a typical RF switch has been reduced from 2.8V to 1.8V, and there has been a demand for products with VDD reduced to 1.2V. However, the key RF N-type field effect MOS tube in the RF switch requires a higher bias voltage (VBIAS) to ensure RF performance. Generally, VBIAS has both positive and negative voltages, and its absolute value is usually in the range of 2.5 to 3.5V. Because the demand for the power supply voltage VDD = 1.2V is much smaller than the range of VBIAS = 2.5 to 3.5V, the main task of the power supply circuit in the RF switch is to boost the external low voltage and then bias the RF tube. When using a charge pump boost architecture, under the requirement of VDD=1.2V, the number of charge pump stages needs to be increased compared to the scenario of VDD=1.8V or 2.8V. However, as the number of charge pump stages increases, the number of flying capacitors (CFLY) and the value of a single capacitor in the charge pump circuit will increase, resulting in the driving capability of the driver tube DCP corresponding to CFLY also needing to be strengthened. That is, the size of the driver tube DCP needs to be increased. When the number of charge pump stages increases and the received signal frequency remains unchanged, the edge of the CFLY voltage square wave will become steeper, indirectly increasing the noise of the RF switch. Therefore, the power supply capacity of the multi-stage charge pump circuit can be enhanced when the RF switch needs to switch channels by enabling the signal generating module 101 to send square wave signals of different powers to the multi-stage charge pump circuit 102. Specifically, the signal generating module 101 in the RF switch power supply circuit can enhance the power supply capacity of the multi-stage charge pump circuit by sending a first square wave signal with a larger frequency to the multi-stage charge pump circuit 102. After the RF switch channel is switched, the signal generating module 101 sends a second square wave signal with a lower frequency to the multi-stage charge pump circuit 102, thereby enabling the RF switch to transmit signals normally.

[0031] Sending a first square wave signal with a relatively large frequency to the multi-stage charge pump circuit can enhance the power supply capability of the multi-stage charge pump circuit, mainly because the size of the equivalent internal resistance of the charge pump is related to the efficiency. Figure 2 This is a schematic diagram of the interstage circuit of a 3-stage full-cycle 8-tube charge pump circuit. Figure 3 It corresponds to Figure 2 The circuit diagram of a single-stage full-cycle 8-tube charge pump is shown in the figure below. Figure 2-3 As shown, 1 st CP (CP1) as an example, charging Phase A, discharging Phase B, and assuming the output I of the multi-stage charge pump circuit (CP) OUTis the average current in the whole cycle, and the charging and discharging time are the same. Then one cycle is divided into A and B:

[0032] Phase A:V CP1 = V DD -I OUT *(R N1 + R N3 )(1)

[0033] Phase B:V O =V DD +V CP1 -I OUT / (2*f CK *C P1 )-I OUT *(R P1 + R P3 )(2)

[0034] Therefore, V O =2*V DD -I OUT *[R P1 +R P3 +R N1 +R N3 +1 / (2*f CK *C P1 )](3)

[0035] From formula (3), the equivalent internal resistance of a single-stage 2-times voltage pump is:

[0036] R ON = R P1 +R P3 +R N1 +R N3 +1 / (2*f CK *C P1 )(4)

[0037] Note that 1 / (2*f CK *C P1 ) is much larger than R P1 +R P3 +R N1 +R N3 The sum of the square wave signals sent to the multi-stage charge pump circuit is f CK and C P1 Talent and R ON Strong correlation, then formula (3) can be simplified as:

[0038] V O = 2*V DD -I OUT / (2*f CK*C P1 )(5)

[0039] From formula (5), we can see that the 2-fold boost output of the 1-stage CP is V O There will be loss item I OUT / (2*f CK *C P1 ).

[0040] It can be concluded that:

[0041] V O1 = 2*V DD -I O1 / (2*f CK *C FLY1 )(6)

[0042] Among them, V O1 and I O1 is the average output voltage and current of CP level 1, C FLY1 It is a flying capacitor with CP level 1.

[0043] When the charge pump circuit changes from 1-stage to n-stage CP, if the loss is kept constant while boosting the voltage to n times V DD , it can be deduced that:

[0044] V ON =(n+1)*V DD -n*I ON / (2*f CK *C FLYN )(7)

[0045] Where n is a positive integer. If the current demand of the RF switch remains unchanged, then I O1 =I O2 =...=I On =I OUT .therefore:

[0046] V ON =(n+1)*V DD -n*I OUT / (2*f CK *C FLYN )(8)

[0047] Without considering the performance such as noise, the voltage loss of the n-level CP must remain unchanged. It can be concluded that:

[0048] 1 / C FLY1 =2 / C FLY2 =3 / C FLY3 =... =n / C FLYN (9)

[0049] According to formula (9), if the driving force and loss remain unchanged, each C of the 2-stage CP FLY The capacitance value of the 3-stage CP should be designed to be twice that of the single-stage CP; FLY The capacitance value of the n-level CP should be designed to be 3 times that of the single-level CP; FLY The capacitance value should be designed to be N times that of a single-stage CP. Considering the C of the n-stage CP FLY The number of CPs is n times that of a single-stage CP, then the C of the n-stage CP FLY The total capacitance is single-stage n 2 Multiple charge pumps such as 2-stage or 3-stage need to be Figure 3 The full-cycle 8-tube CP circuit is cascaded, and the output capacitor of the previous CP is changed to a small capacitor C S , used to adjust the voltage ripple between CP stages, the output capacitor of the final CP stage is a large capacitor C O . It can be seen that the higher the number of stages of the charge pump circuit, the higher the demand for the driving capability of the flying capacitor. If the width-to-length ratio of the device used for driving is directly increased, although the charging capability of the flying capacitor can be improved, the transient waveform of the square wave voltage of the flying capacitor becomes steeper or even oscillates at the rising edge. When the RF switch transmits a signal, the high-frequency component of the steeply changing voltage at the square wave edge of the flying capacitor enters the RF channel through circuit parasitics and other couplings, causing noise problems. Taking into account both the noise problem and the driving problem, the square wave frequency f input by the signal generation module 101 can be changed. CK The RF switch can start quickly and transmit low-noise signals. When the RF switch is transmitting signals stably and is in the non-switching time, the current demand on the power supply circuit is small. At this time, the signal generation module 101 uses a second square wave signal with a lower frequency to ensure stable output, and the slow frequency f CK The noise is small, which is more conducive to the RF path to achieve low noise performance. When the RF switch stops transmitting signals and is in the RF channel switching time, when the RF switch channel switching starts, the signal generation module 101 outputs a first square wave signal with a higher frequency, so that the multi-stage charge pump circuit quickly boosts the voltage, and since the RF switch stops transmitting signals when switching channels, no noise is generated.

[0050] Specifically, the ratio of the frequency of the first square wave signal to the frequency of the second square wave signal is in the range of [3,12]. This can better drive the multi-stage charge pump circuit, thereby improving the channel switching efficiency of the radio frequency switch.

[0051] Specifically, the frequency interval of the second square wave signal is [1 MHz, 5 MHz], and correspondingly, the frequency interval of the first square wave signal is [3 MHz, 60 MHz].

[0052] By setting the frequency interval of the second square wave signal to [1 MHz, 5 MHz], low noise can be ensured while ensuring the transmission of the RF switch signal.

[0053] In the embodiment of the present application, the signal generating module 101 sends a first square wave signal with a higher frequency to the multi-stage charge pump circuit during the channel switching process of the RF switch, and sends a second square wave signal with a lower frequency to the multi-stage charge pump circuit after the RF switch completes the channel switching, so that the RF switch can complete fast channel switching and generate lower noise after the channel switching is completed.

[0054] In a possible implementation, the signal generating module 101 includes: an enabling signal generating module 1011 and a square wave oscillator 1012. The enabling signal generating module 1011 is used to generate a first enabling signal in response to a channel switching start signal of the RF switch, and to generate a second enabling signal in response to a channel switching end signal of the RF switch. The square wave oscillator 1012 is used to generate a first square wave signal according to the first enabling signal when the enabling signal generating module 1011 generates a first enabling signal, and to generate a second square wave signal according to the second enabling signal when the enabling signal generating module 1011 generates a second enabling signal.

[0055] The specific manner in which the signal generating module 101 generates the first square wave signal and the second square wave signal may be that the enable signal generating module 1011 outputs different enable signals according to whether the RF switch is in a channel switching state. For example, the enable signal generating module 1011 outputs a first enable signal in response to a channel switching start signal of the RF switch, and the enable signal generating module 1011 generates a second enable signal in response to a channel switching end signal of the RF switch. The square wave oscillator 1012 (oscillator) may generate a first square wave signal according to the first enable signal and generate a second square wave signal according to the second enable signal, thereby realizing a quick start of the RF switch.

[0056] In the embodiment of the present application, the enable signal generation module 1011 generates different enable signals in response to the signal indicating the state of the RF switch, thereby controlling the square wave oscillator 1012 to output a first square wave signal when the RF switch needs to switch channels, and to output a second square wave signal when the RF switch needs to transmit signals.

[0057] Figure 4 is a schematic diagram of a radio frequency switch power supply circuit including an inverter provided in an embodiment of the present application, such as Figure 4 As shown, the multi-stage charge pump circuit 102 includes: an inverter 1021 and at least two charge pumps connected in series.

[0058] The charge pump includes: two drivers, two flying capacitors, a control switch and an output capacitor. The two drivers include a first driver 1022-1 and a second driver 1022-2, and the two flying capacitors include a first flying capacitor 1023-1 and a second flying capacitor 1023-2. The output end of the first driver 1022-1 is electrically connected to the first end of the first flying capacitor 1023-1, and the output end of the second driver 1022-2 is electrically connected to the first end of the second flying capacitor 1023-2. The control switch 1024 is electrically connected to the second end of the first flying capacitor 1023-1 and the second end of the second flying capacitor 1023-2 respectively. The first end of the output capacitor 1025 is electrically connected to the control switch 1024, and the second end of the output capacitor 1025 is grounded. The first end of the output capacitor 1025 in the non-final charge pump of at least two charge pumps is electrically connected to the control switch 1024 in the next charge pump, and the first end of the output capacitor 1025 in the final charge pump of at least two charge pumps is electrically connected to the RF switch 200. The control end of the first driver 1022-1 is electrically connected to the output end of the square wave oscillator 1012, the input end of the inverter 1021 is electrically connected to the output end of the square wave oscillator 1012, and the output end of the inverter 1021 is electrically connected to the control end of the second driver 1022-2. The first driver 1022-1 is used to charge the connected first flying capacitor 1023-1 according to the square wave signal output by the square wave oscillator 1012. The second driver 1022-2 is used to charge the connected second flying capacitor 1023-2 according to the square wave signal output by the inverter 1021. The control switch 1024 is used to control the charging and discharging of the two flying capacitors, wherein the output capacitor 1025 is charged when the two flying capacitors are discharged.

[0059] The multi-stage charge pump circuit 102 can be composed of at least two charge pumps connected in series. The structure of each charge pump is the same, including a first driver 1022-1, a second driver 1022-2, a first flying capacitor 1023-1, a second flying capacitor 1023-2, a control switch 1024 and an output capacitor 1025. After receiving the high level or low level signal output by the square wave oscillator 1012, the first driver 1022-1 and the second driver 1022-2 will charge the first flying capacitor 1023-1 and the second flying capacitor 1023-2 according to the power supply respectively. When the square wave oscillator 1012 outputs a level signal opposite to that when the driver is working, the flying capacitor will discharge and input the output capacitor 1025 through the control switch 1024. It can be seen that in this case, in one clock cycle, only half a cycle can provide current to the output capacitor 1025. In order to improve efficiency, two drivers, two flying capacitors, a control switch 1024 and an output capacitor 1025 are provided in the charge pump, and one of the drivers is connected to the output end of the inverter 1021. Figure 4Among them, the exemplary second driver 1022-2 is connected to the output end of the inverter 1021. This configuration can improve the charging efficiency of the flying capacitor.

[0060] Specifically, the capacitance value range of the output capacitor 1025 in the non-final charge pump in at least two charge pumps is [1 pF, 4 pF], and the capacitance value of the output capacitor 1025 in the final charge pump in at least two charge pumps is greater than or equal to 40 pF.

[0061] Since the output capacitor 1025 in the non-final charge pump in at least two charge pumps serves as an inter-electrode capacitor and is only used to adjust the voltage ripple between charge pump stages, its capacitance value does not need to be too large, and the capacitance value range can be set to [1pF, 4pF]. The output capacitor 1025 in the final charge pump in at least two charge pumps serves as the output end, and requires a sufficiently large capacitance value, which is usually set to be no less than 40pF.

[0062] Specifically, the capacitance values ​​of the first flying capacitor and the second flying capacitor are greater than or equal to 8 pF.

[0063] According to the derivation of the above formula (9), in the multi-stage charge pump circuit 102, the higher the charge pump stage number, the higher the total capacitance of the flying capacitor in the corresponding stage number. Therefore, in the multi-stage charge pump circuit 102, the capacitance value of the flying capacitor is at least 8pF.

[0064] In an embodiment of the present application, an inverter 1021 is provided in the multi-stage charge pump circuit 102, and two drivers and two flying capacitors are provided in the charge pump. By controlling a group of drivers and flying capacitors through the inverter 1021, the charging efficiency of the flying capacitors can be doubled, thereby improving the driving capability of the multi-stage charge pump circuit 102.

[0065] Figure 5 is a circuit diagram of a radio frequency switch power supply circuit provided in an embodiment of the present application, such as Figure 5 As shown, the control switch 1024 includes: a first MOS transistor 10241 , a second MOS transistor 10242 , a third MOS transistor 10243 and a fourth MOS transistor 10244 .

[0066] The output end of the first MOS tube 10241, the input end of the third MOS tube 10243, the control end of the second MOS tube 10242, and the control end of the fourth MOS tube 10244 are electrically connected to the second end of the first flying capacitor, the input end of the first MOS tube 10241 is electrically connected to the input end of the second MOS tube 10242 and is grounded, the control end of the first MOS tube 10241, the control end of the third MOS tube 10243, the output end of the second MOS tube 10242, and the input end of the fourth MOS tube 10244 are electrically connected to the second end of the second flying capacitor, and the output ends of the third MOS tube 10243 and the fourth MOS tube 10244 are electrically connected to the first end of the output capacitor 1025.

[0067] There are two sets of driver and flying capacitor combinations in each charge pump. After receiving the high or low level signal output by the square wave oscillator 1012, the driver of one set of drivers outputs V according to the power supply. LDO The flying capacitor is charged. At the same time, another combination of a driver and a flying capacitor receives a signal output by the inverter 1021 that is opposite to the level of the square wave oscillator 1012. At this time, the flying capacitor in the other group will discharge and charge the output capacitor 1025 by controlling the switch 1024.

[0068] It should be noted that since multiple charge pumps are connected in series, the object that is charged when the flying capacitor in the non-final charge pump is discharged is actually the output capacitor 1025 in the final charge pump. The output capacitor in the non-final charge pump is only used to adjust the voltage ripple between charge pump stages.

[0069] In the embodiment of the present application, the first MOS tube 10241 and the third MOS tube 10243, and the second MOS tube 10242 and the fourth MOS tube 10244 constitute two groups of inverting switches, which can clamp each other's voltage to achieve automatic switching of the first flying capacitor 1023-1 and the second flying capacitor 1023-2 to charge the output capacitor 1025 within a cycle.

[0070] Figure 6 is a schematic diagram of a radio frequency switch power supply circuit including a main drive inverter provided in an embodiment of the present application, such as Figure 6 As shown, the first driver 1022-1 and the second driver 1022-2 have the same structure, and both include: a main driving inverter, at least one auxiliary driving inverter, two analog switches and a power supply 10221. The two analog switches include a first analog switch and a second analog switch.

[0071] Taking the first driver 1022-1 as an example: the driving end of the main driving inverter is connected to the output end of the square wave oscillator 1012, the input end of the main driving inverter is electrically connected to the first end of the power supply 10221, the other end of the power supply 10221 is connected to the ground end, the power input end and the ground end of the main driving inverter are electrically connected to the first ends of the two analog switches respectively, and the power input end and the ground end of the auxiliary driving inverter are electrically connected to the second ends of the two analog switches respectively. Specifically, the input end of the main driving inverter and the input end of the auxiliary driving inverter are electrically connected to the first end and the second end of the first analog switch respectively, and the ground end of the main driving inverter and the ground end of the auxiliary driving inverter are electrically connected to the first end and the second end of the second analog switch respectively.

[0072] The driving end of the auxiliary driving inverter is electrically connected to the output end of the square wave oscillator 1012 (the driving end of the auxiliary driving inverter in the second driver 1022-2 is electrically connected to the output end of the inverter 1021), the output end of the auxiliary driving inverter is electrically connected to the first end of the first flying capacitor 1023-1 (the output end of the auxiliary driving inverter in the second driver 1022-2 is electrically connected to the first end of the second flying capacitor 1023-2), and the control end of the analog switch is electrically connected to the output end of the enable signal generating module 1011. The analog switch is used to close when receiving the first enable signal to electrically connect the auxiliary driving inverter to the main driving inverter, and to open when receiving the second enable signal to disconnect the auxiliary driving inverter from the main driving inverter.

[0073] The power supply 10221 may be the output V described in the above embodiment. LDO The power supply V.

[0074] The driver may be provided with at least one auxiliary drive inverter, and two analog switches are used to control whether the auxiliary drive inverter is electrically connected to the main drive inverter. The analog switch is controlled by the enable signal output by the enable signal generation module 1011. When the analog switch receives the first enable signal, the driver needs to be driven with a higher power. At this time, the analog switch is closed, and the auxiliary drive inverter is connected. The auxiliary drive inverter and the main drive inverter are driven together to achieve a higher power drive, thereby achieving fast channel switching of the RF switch. When the analog switch receives the second enable signal, the driver needs to be driven with a lower power. At this time, the analog switch is disconnected, and only the main drive inverter in the driver is driven, thereby achieving low-noise signal transmission of the RF switch.

[0075] Specifically, the main driving inverter includes: a fifth MOS tube 10222 and a sixth MOS tube 10223 , the auxiliary driving inverter includes: a seventh MOS tube 10224 and an eighth MOS tube 10225 , the first analog switch includes: a ninth MOS tube 10226 , and the second analog switch includes: a tenth MOS tube 10227 .

[0076] Taking the main driving inverter in the first driver 1022-1 as an example, the control end of the fifth MOS tube 10222, the control end of the sixth MOS tube 10223, the control end of the seventh MOS tube 10224, and the control end of the eighth MOS tube 10225 are electrically connected to the output end of the square wave oscillator 1012, the input end of the fifth MOS tube 10222 is electrically connected to the first end of the power supply 10221 and the input end of the ninth MOS tube 10226, the other end of the power supply 10221 is grounded, and the output end of the fifth MOS tube 10222, the output end of the sixth MOS tube 10223, the output end of the seventh MOS tube 10224, and the output end of the eighth MOS tube 10225 are electrically connected to the first end of the first flying capacitor 1023-1 (the second driver The output end of the fifth MOS tube 10222, the output end of the sixth MOS tube 10223, the output end of the seventh MOS tube 10224, and the output end of the eighth MOS tube 10225 in the main driving inverter in 1022-2 are electrically connected to the first end of the second flying capacitor 1023-2, the input end of the sixth MOS tube 10223 is electrically connected to the input end of the tenth MOS tube 10227 and is grounded, the control ends of the ninth MOS tube 10226 and the tenth MOS tube 10227 are electrically connected to the output end of the enable signal generating module 1011, the output end of the ninth MOS tube 10226 is electrically connected to the input end of the seventh MOS tube 10224, and the output end of the tenth MOS tube 10227 is electrically connected to the input end of the eighth MOS tube 10225.

[0077] In the embodiment of the present application, by providing a certain number of auxiliary driving inverters as required, the main driving inverter can be auxiliary driven, thereby improving the driving capability of the main driving inverter.

[0078] It should be noted that, under the premise of no conflict, the various embodiments and / or the technical features in the various embodiments described in this application can be arbitrarily combined with each other, and the technical solution obtained after the combination should also fall within the protection scope of this application.

[0079] It should be understood that the specific examples in the embodiments of the present application are only to help those skilled in the art to better understand the embodiments of the present application, rather than to limit the scope of the embodiments of the present application. Those skilled in the art can make various improvements and modifications based on the above embodiments, and these improvements or modifications all fall within the scope of protection of the present application.

[0080] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A radio frequency switch power supply circuit, characterized in that: include: A signal generation module and a multi-stage charge pump circuit; The signal generating module is used to send a first square wave signal to the multi-stage charge pump circuit during the channel switching of the radio frequency switch, and send a second square wave signal to the multi-stage charge pump circuit after the radio frequency switch completes the channel switching, wherein the frequency of the first square wave signal is greater than the frequency of the second square wave signal; The multi-stage charge pump circuit is used to boost the input voltage according to the signal sent by the signal generating module to supply power to the radio frequency switch.

2. The radio frequency switch power supply circuit according to claim 1, characterized in that: The signal generating module comprises: an enabling signal generating module and a square wave oscillator; The enable signal generating module is used to generate a first enable signal in response to a channel switching start signal of the RF switch, and to generate a second enable signal in response to a channel switching end signal of the RF switch; The square wave oscillator is used to generate the first square wave signal according to the first enable signal when the enable signal generating module generates the first enable signal, and to generate the second square wave signal according to the second enable signal when the enable signal generating module generates the second enable signal.

3. The radio frequency switch power supply circuit according to claim 2, characterized in that: The multi-stage charge pump circuit comprises: an inverter and at least two charge pumps connected in series; The charge pump comprises: two drivers, two flying capacitors, a control switch and an output capacitor, the two drivers comprise a first driver and a second driver, the two flying capacitors comprise a first flying capacitor and a second flying capacitor; The output end of the first driver is electrically connected to the first end of the first flying capacitor, and the output end of the second driver is electrically connected to the first end of the second flying capacitor; The control switch is electrically connected to the second end of the first flying capacitor and the second end of the second flying capacitor respectively; The first end of the output capacitor is electrically connected to the control switch, and the second end of the output capacitor is grounded; The first end of the output capacitor in the non-final charge pump of the at least two charge pumps is electrically connected to the control switch in the next-stage charge pump, and the first end of the output capacitor in the final charge pump of the at least two charge pumps is electrically connected to the radio frequency switch; The control end of the first driver is electrically connected to the output end of the square wave oscillator, the input end of the inverter is electrically connected to the output end of the square wave oscillator, and the output end of the inverter is electrically connected to the control end of the second driver; The first driver is used to charge the connected first flying capacitor according to the square wave signal output by the square wave oscillator; The second driver is used to charge the connected second flying capacitor according to the square wave signal output by the inverter; The control switch is used to control the two flying capacitors to charge and discharge, wherein the output capacitor is charged when the two flying capacitors are discharged.

4. The radio frequency switch power supply circuit according to claim 3, characterized in that: The capacitance value of the output capacitor in the non-final-stage charge pump among the at least two charge pumps is smaller than the capacitance value of the output capacitor in the final-stage charge pump among the at least two charge pumps.

5. The radio frequency switch power supply circuit according to claim 3, characterized in that: The control switch comprises: a first MOS tube, a second MOS tube, a third MOS tube and a fourth MOS tube; The output end of the first MOS tube, the input end of the third MOS tube, the control end of the second MOS tube, and the control end of the fourth MOS tube are electrically connected to the second end of the first flying capacitor, the input end of the first MOS tube is electrically connected to the input end of the second MOS tube and is grounded, the control end of the first MOS tube, the output end of the second MOS tube, the control end of the third MOS tube, and the input end of the fourth MOS tube are electrically connected to the second end of the second flying capacitor, and the output ends of the third MOS tube and the fourth MOS tube are electrically connected to the first end of the output capacitor.

6. The radio frequency switch power supply circuit according to claim 3, characterized in that: The driver comprises: a main driving inverter, at least one auxiliary driving inverter, two analog switches and a power supply, wherein the two analog switches comprise a first analog switch and a second analog switch; The driving end of the main driving inverter is electrically connected to the output end of the square wave oscillator, the input end of the main driving inverter is electrically connected to the first end of the power supply, and the other end of the power supply is connected to the ground; The input end of the main driving inverter and the input end of the auxiliary driving inverter are electrically connected to the first end and the second end of the first analog switch respectively, the ground end of the main driving inverter and the ground end of the auxiliary driving inverter are electrically connected to the first end and the second end of the second analog switch respectively, the driving end of the auxiliary driving inverter is electrically connected to the output end of the square wave oscillator or the output end of the inverter, the output end of the auxiliary driving inverter is electrically connected to the first end of the first flying capacitor or the second flying capacitor, and the control end of the analog switch is electrically connected to the output end of the enable signal generating module; The analog switch is used to close when receiving the first enable signal to electrically connect the auxiliary drive inverter to the main drive inverter, and to open when receiving the second enable signal to disconnect the auxiliary drive inverter from the main drive inverter.

7. The radio frequency switch power supply circuit according to claim 6, characterized in that: The main driving inverter includes: a fifth MOS tube and a sixth MOS tube, the auxiliary driving inverter includes: a seventh MOS tube and an eighth MOS tube, the first analog switch includes: a ninth MOS tube, and the second [AW20240033ICN1][HS2411253CCN] analog switch includes a tenth MOS tube; The control end of the fifth MOS tube, the control end of the sixth MOS tube, the control end of the seventh MOS tube, and the control end of the eighth MOS tube are electrically connected to the output end of the square wave oscillator; the input end of the fifth MOS tube is electrically connected to the first end of the power supply and the input end of the ninth MOS tube, the other end of the power supply is grounded, the output end of the fifth MOS tube, the output end of the sixth MOS tube, the output end of the seventh MOS tube, and the output end of the eighth MOS tube are electrically connected to the first end of the first flying capacitor or the second flying capacitor; the input end of the sixth MOS tube is electrically connected to the input end of the tenth MOS tube and is grounded; the control ends of the ninth MOS tube and the tenth MOS tube are electrically connected to the output end of the enable signal generating module; the output end of the ninth MOS tube is electrically connected to the input end of the seventh MOS tube, and the output end of the tenth MOS tube is electrically connected to the input end of the eighth MOS tube.

8. The radio frequency switch power supply circuit according to claim 1, characterized in that: The ratio of the frequency of the first square wave signal to the frequency of the second square wave signal is in the range of [3, 12].

9. The radio frequency switch power supply circuit according to claim 8, characterized in that: The frequency interval of the second square wave signal is [1 MHz, 5 MHz].

10. The radio frequency switch power supply circuit according to claim 3, characterized in that: The capacitance value interval of the output capacitor in the non-final charge pump of the at least two charge pumps is [1pF, 4pF], and the capacitance value of the output capacitor in the final charge pump of the at least two charge pumps is greater than or equal to 40pF.

11. The radio frequency switch power supply circuit according to claim 3, characterized in that: The capacitance values ​​of the first flying capacitor and the second flying capacitor are greater than or equal to 8 pF.

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