Output matching circuit, amplifier and electronic equipment

Abstract

The embodiment of the invention provides an output matching circuit, an amplifier and electronic equipment. The output matching circuit is applied to the amplifier. The output matching circuit is used for receiving the amplified signal, determining a working frequency band in a plurality of frequency bands corresponding to the amplified signal, performing output impedance matching on the signal of the working frequency band, and outputting a target signal; the working frequency band is any one frequency band in a plurality of frequency bands; the output matching circuit comprises a capacitance switching circuit, a first inductor and a first capacitor, the input end of the capacitance switching circuit is used for receiving the amplified signal, the output end of the capacitance switching circuit is connected with the first end of the first inductor and the first end of the first capacitor, and the second end of the first inductor is connected with the power supply end; the second end of the first capacitor is used for outputting a target signal; wherein the capacitance switching circuit is used for filtering a signal of a target frequency band by adjusting an equivalent inductance value or an equivalent capacitance value of the capacitance switching circuit.

Description

Technical Field

[0001] This disclosure relates to the field of integrated circuit technology, and more particularly to an output matching circuit, amplifier, and electronic device. Background Technology

[0002] As an important module of radio frequency front-end circuits, amplifiers are increasingly important in the context of the advent of the 5G era. Communication protocols are becoming more and more complex, and the performance requirements inside and outside the frequency band are also becoming higher and higher. This requires amplifiers to have high gain, low noise figure and high linearity in multiple operating frequency bands, while also being able to suppress out-of-band interference signals to ensure receiving sensitivity.

[0003] In related technologies, in order to achieve operation in multiple frequency bands, a switching device needs to be added to the output of the amplifier to ensure that each operating frequency band has a sufficiently high gain. At the same time, in order to suppress out-of-band interference signals in other frequency bands when operating in a certain frequency band, an additional switchable filter network needs to be designed in the input or output matching network to achieve interference suppression in specific frequency bands and reduce the interference power received by subsequent receiver link devices. As a result, the circuit design complexity and chip area are increased, and the performance of the amplifier is sacrificed. Summary of the Invention

[0004] This disclosure provides an output matching circuit, an amplifier, and an electronic device.

[0005] In a first aspect, embodiments of this disclosure provide an output matching circuit applied to an amplifier; The output matching circuit is used to receive the amplified signal, determine the working frequency band among multiple frequency bands corresponding to the amplified signal, perform output impedance matching on the signal of the working frequency band, and output the target signal; the working frequency band is any one of the multiple frequency bands. The output matching circuit includes a capacitor switching circuit, a first inductor, and a first capacitor. The input terminal of the capacitor switching circuit is used to receive the amplified signal. The output terminal of the capacitor switching circuit is connected to the first terminal of the first inductor and the first terminal of the first capacitor, respectively. The second terminal of the first inductor is connected to the power supply terminal, and the second terminal of the first capacitor is used to output the target signal. Wherein: The capacitor switching circuit is used to filter signals in the target frequency band by adjusting the equivalent inductance or equivalent capacitance value of the capacitor switching circuit.

[0006] In some embodiments, the capacitor switching circuit includes a second inductor and N capacitor switching sub-circuits connected in parallel. The first terminal of the second inductor is connected to the first terminals of each of the N capacitor switching sub-circuits and serves as the input terminal of the capacitor switching circuit. The second terminal of the second inductor is connected to the second terminals of each of the N capacitor switching sub-circuits and serves as the output terminal of the capacitor switching circuit. Wherein: The output matching circuit is further configured to activate M of the N capacitor switching sub-circuits and determine the operating frequency band among the plurality of frequency bands corresponding to the amplified signal; N is an integer greater than or equal to 1, and M is an integer greater than or equal to 1 and less than or equal to N.

[0007] In some embodiments, the capacitor switching circuit is further configured to activate M of the N capacitor switching sub-circuits to determine the equivalent inductance or equivalent capacitance value of the capacitor switching circuit.

[0008] In some embodiments, the capacitor switching sub-circuit includes a second capacitor and a switching circuit connected in series; the first terminal of the switching circuit serves as the first terminal of the capacitor switching sub-circuit, the second terminal of the switching circuit is connected to the first terminal of the second capacitor, and the second terminal of the second capacitor serves as the second terminal of the capacitor switching sub-circuit.

[0009] In some embodiments, the capacitor switching circuit is further configured to determine the resonant frequency based on the inductance value of the second inductor and the capacitance value of the second capacitor in the activated capacitor switching sub-circuit; The target frequency band includes the resonant frequency.

[0010] In some embodiments, the capacitor switching circuit is further configured to, when the operating frequency is less than the resonant frequency, determine the inductance value of the second inductor and the capacitance value of the second capacitor in the conducted capacitor switching sub-circuit as the equivalent inductance value of the capacitor switching circuit, and filter signals greater than the operating frequency. Alternatively, when the operating frequency is greater than the resonant frequency, the inductance value of the second inductor and the capacitance value of the second capacitor in the activated capacitor switching sub-circuit are determined as the equivalent capacitance value of the capacitor switching circuit, and the signal less than the operating frequency is filtered. The operating frequency band includes the operating frequency.

[0011] In some embodiments, the first inductor and the second inductor are wound in the same coil.

[0012] In a second aspect, embodiments of this disclosure provide an amplifier, the amplifier including an amplification circuit and an output matching circuit as described in any one of the first aspects, the amplification circuit being connected to the output matching circuit.

[0013] In some embodiments, the amplifier circuit includes a common-source transistor and a common-gate transistor; the first terminal of the common-source transistor is connected to a ground terminal, the second terminal of the common-source transistor is connected to the first terminal of the common-gate transistor, the second terminal of the common-gate transistor is connected to the output matching circuit and used to output an amplified signal, the control terminal of the common-source transistor is used to receive an input signal, and the control terminal of the common-gate transistor is used to receive a bias voltage.

[0014] Thirdly, embodiments of this disclosure provide an electronic device comprising an amplifier as described in any one of the second aspects.

[0015] This disclosure provides an output matching circuit, an amplifier, and an electronic device. The output matching circuit is applied to the amplifier. The output matching circuit receives an amplified signal, determines a working frequency band from multiple frequency bands corresponding to the amplified signal, performs output impedance matching on the signal in the working frequency band, and outputs a target signal. The working frequency band is any one of the multiple frequency bands. The output matching circuit includes a capacitor switching circuit, a first inductor, and a first capacitor. The input terminal of the capacitor switching circuit receives the amplified signal, and the output terminal is connected to the first terminal of the first inductor and the first terminal of the first capacitor, respectively. The second terminal of the first inductor is connected to a power supply terminal, and the second terminal of the first capacitor is used to output the target signal. The capacitor switching circuit filters the signal in the target frequency band by adjusting the equivalent inductance or equivalent capacitance value of the capacitor switching circuit. By reusing the capacitor switching circuit used for frequency band switching in the output matching circuit for filtering, the output matching circuit achieves both frequency band switching and filtering capabilities. This eliminates the need for additional filtering circuits to meet specific filtering requirements at different operating frequencies, reducing the impact of adding additional matching components on performance, lowering circuit complexity, reducing layout area, and ultimately reducing costs. Attached Figure Description

[0016] Figure 1 A schematic diagram of an amplifier structure provided for related technologies; Figure 2 A schematic diagram of the structure of an output matching circuit provided in an embodiment of this disclosure. Figure 1 ; Figure 3 A schematic diagram of the structure of an output matching circuit provided in an embodiment of this disclosure. Figure 2 ; Figure 4This is an equivalent schematic diagram of a capacitor switching circuit provided in an embodiment of the present disclosure; Figure 5 A schematic diagram of a filtering curve provided in an embodiment of this disclosure; Figure 6 A schematic diagram of the structure of an amplifier provided in this disclosure embodiment. Figure 1 ; Figure 7 A schematic diagram of the structure of an amplifier provided in this disclosure embodiment. Figure 2 ; Figure 8 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this disclosure. Detailed Implementation

[0017] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for explaining the relevant applications and are not intended to limit the scope of this disclosure. Furthermore, it should be noted that, for ease of description, only the parts relevant to the relevant applications are shown in the accompanying drawings.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used herein is for the purpose of describing embodiments of this disclosure only and is not intended to be limiting of this disclosure.

[0019] In the following description, references are made to “some embodiments,” which describe a subset of all possible embodiments. However, it is understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0020] It should be noted that the terms "first, second, third" used in the embodiments of this disclosure are merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first, second, third" can be interchanged in a specific order or sequence where permitted, so that the embodiments of this disclosure described herein can be implemented in an order other than that illustrated or described herein.

[0021] In related technologies, the output matching network (i.e., output matching circuit) of the amplifier is equipped with a switching device to select the operating frequency band and ensure that each operating frequency band has a sufficiently high gain. An additional switchable filter network (i.e., switchable filter circuit) is also designed in the amplifier to achieve interference suppression in specific frequency bands. This leads to increased circuit design complexity and chip area, sacrifices amplifier performance, and thus increases cost.

[0022] See Figure 1 It shows a schematic diagram of the structure of an amplifier provided by related technologies. For example... Figure 1 As shown, amplifier 10 includes an input matching circuit 11, an amplification circuit 12, an output matching circuit 13, a filter circuit 14, and a switchable gain attenuation circuit 15. The amplification circuit 12 includes a first transistor 121 and a second transistor 122. The output matching circuit 13 includes an inductor 131, a capacitor 132, a switch 133, and a capacitor 134. The filter circuit 14 includes a capacitor 141, a switch 142, and an inductor 143. For specific connection relationships, please refer to [reference needed]. Figure 1 .

[0023] Here, the first transistor 121 and the second transistor 122 can be N-type metal-oxide-semiconductor field-effect transistors (NMOS transistors). In addition, the input matching circuit 11 is specifically a switchable input matching circuit with filtering function, and the filter circuit 14 is specifically a switchable filter circuit.

[0024] It should be noted that capacitor 132 and switch 133 are connected in series, while inductor 131 is connected in parallel with capacitor 132 and switch 133. By switching switch 133 in different frequency bands, different capacitance values ​​can be switched, thereby changing the equivalent inductance value of the parallel network formed by inductor 131, capacitor 132, and switch 133, and thus changing the output matching frequency. Capacitor 141, switch 142, and inductor 143 are connected in series to form an inductor-capacitor (LC) filter circuit.

[0025] In related technologies, because the inductor 131 in the output matching circuit 13 is very sensitive to the effects of gain and bandwidth, and the quality factor (Q value) and resonant frequency of the equivalent inductor obtained after the parallel capacitor 132 are correspondingly reduced, it is necessary to sacrifice some of the bandwidth and gain performance of the output matching. In addition, if further suppression of out-of-band interference signals is to be considered, an additional cutaway LC filter circuit (i.e., filter circuit 14) needs to be added to the amplifier 10. However, the filter circuit 14 not only requires an additional inductor area, but also adds additional losses to the output matching circuit 13, thereby affecting the overall performance of the amplifier 10.

[0026] Based on this, this disclosure provides an output matching circuit applied to an amplifier. The output matching circuit receives an amplified signal, determines a working frequency band among multiple frequency bands corresponding to the amplified signal, performs output impedance matching on the signal in the working frequency band, and outputs a target signal. The working frequency band is any one of the multiple frequency bands. The output matching circuit includes a capacitor switching circuit, a first inductor, and a first capacitor. The input terminal of the capacitor switching circuit receives the amplified signal, and the output terminal is connected to the first terminal of the first inductor and the first terminal of the first capacitor, respectively. The second terminal of the first inductor is connected to a power supply terminal, and the second terminal of the first capacitor is used to output the target signal. The capacitor switching circuit filters the signal in the target frequency band by adjusting the equivalent inductance or equivalent capacitance value of the capacitor switching circuit. By reusing the capacitor switching circuit used for frequency band switching in the output matching circuit for filtering, the output matching circuit achieves both frequency band switching and filtering capabilities. This eliminates the need for additional filtering circuits to meet specific filtering requirements at different operating frequencies, reducing the impact of adding additional matching components on performance, lowering circuit complexity, reducing layout area, and ultimately reducing costs.

[0027] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings.

[0028] In one embodiment of this disclosure, see [link to embodiment]. Figure 2 It shows a schematic diagram of the structure of an output matching circuit provided in an embodiment of this disclosure. Figure 1 .like Figure 2 As shown, the output matching circuit 20 is used to receive the amplified signal, determine the working frequency band among multiple frequency bands corresponding to the amplified signal, perform output impedance matching on the signal in the working frequency band, and output the target signal; the working frequency band can be any one of the multiple frequency bands. The output matching circuit 20 may include a capacitor switching circuit 21, a first inductor 22, and a first capacitor 23. The input terminal of the capacitor switching circuit 21 is used to receive the amplified signal. The output terminal of the capacitor switching circuit 21 is connected to the first terminal of the first inductor 22 and the first terminal of the first capacitor 23, respectively. The second terminal of the first inductor 22 is connected to the power supply terminal, and the second terminal of the first capacitor 23 is used to output the target signal. The capacitor switching circuit 21 is used to filter the signal of the target frequency band by adjusting the equivalent inductance or equivalent capacitance value of the capacitor switching circuit 21.

[0029] This disclosure provides an output matching circuit 20, specifically a multi-frequency amplifier output circuit with filtering capabilities, i.e., an output matching circuit with frequency band switching and filtering functions. The output matching circuit 20 can be applied to an amplifier, specifically a multi-frequency amplifier. The multi-frequency amplifier can cover multiple preset frequency bands and simultaneously support the operation of multiple discrete frequency bands.

[0030] It should be noted that the amplified signal is the signal obtained by amplifying the input signal through the amplification circuit in the amplifier; the operating frequency band refers to the frequency band in which the amplifier operates and amplifies the signal. In addition, the target frequency band can be one of the multiple frequency bands corresponding to the amplified signal, or it can be an out-of-band interference signal, without specific limitations.

[0031] Here, the first inductor 22 can be represented by Lchock, and the first capacitor 23 can be represented by Cout.

[0032] It should also be noted that the output matching circuit 20 can select from multiple frequency bands corresponding to the amplified signal and perform output impedance matching to obtain the target signal. Output impedance matching refers to the impedance adjustment between the amplifier's output terminal and the load (e.g., antenna, speaker, etc.) to achieve maximum power transmission and reduce signal reflection.

[0033] It should also be noted that the capacitor switching circuit 21 includes at least one capacitor, and the number of capacitors connected to the output matching circuit 20 can be changed. By changing the number of capacitors connected to the output matching circuit 20, the operating frequency band can be determined among multiple frequency bands corresponding to the amplified signal, and the equivalent inductance or equivalent capacitance value of the capacitor switching circuit 21 can be changed. Specifically, different numbers of capacitors connected to the output matching circuit 20 result in different impedances of the output matching circuit 20, and different equivalent inductance or equivalent capacitance values ​​of the capacitor switching circuit 21, thereby enabling frequency band switching; and different numbers of capacitors connected to the output matching circuit 20 result in different resonant frequencies of the capacitor switching circuit 21, thereby enabling filtering.

[0034] Alternatively, depending on the circumstances, the capacitor switching circuit 21 can be equivalent to an inductor to obtain its equivalent inductance value, or it can be equivalent to a capacitor to obtain its equivalent capacitance value. No specific limitation is made in this regard.

[0035] In this embodiment, the output matching circuit 20 not only achieves frequency band switching but also has filtering capabilities. Compared to Figure 1In this invention, a filter circuit 14 is added to the output of the output matching circuit 13 to perform out-of-band suppression. The capacitor switching circuit 21 used for frequency band switching in the output matching circuit 20 is reused, so that no additional switchable LC filter circuit is needed to meet the specific filtering requirements at different operating frequencies. This reduces the impact of adding additional matching devices on performance, and also reduces the complexity of the circuit, reduces the layout area, and thus reduces costs.

[0036] In some embodiments, such as Figure 3 As shown, the capacitor switching circuit 21 may include a second inductor 211 and N capacitor switching sub-circuits 212 connected in parallel (only one is shown in the figure). The first end of the second inductor 211 is connected to the first end of each of the N capacitor switching sub-circuits 212 and serves as the input terminal of the capacitor switching circuit 21. The second end of the second inductor 211 is connected to the second end of each of the N capacitor switching sub-circuits 212 and serves as the output terminal of the capacitor switching circuit 21. The output matching circuit 20 is also used to turn on M capacitor switching sub-circuits 212 in N capacitor switching sub-circuits 212, and determine the working frequency band among multiple frequency bands corresponding to the amplified signal; N is an integer greater than or equal to 1, and M is an integer greater than or equal to 1 and less than or equal to N.

[0037] Here, the second inductor 211 can be represented by Lout.

[0038] It should be noted that in this embodiment, the values ​​of N and M are not specifically limited. All N capacitor switching sub-circuits 212 can be turned on or partially turned on. For example, if N=3, one capacitor switching sub-circuit 212 can be turned on, or two capacitor switching sub-circuits 212 can be turned on, or all three capacitor switching sub-circuits 212 can be turned on. Here, changing the values ​​of N and M can change the number of capacitors connected to the output matching circuit 20. Based on the determined values ​​of N and M, the number of capacitors connected to the output matching circuit 20 can be determined.

[0039] For example, the equivalent inductance value of the capacitor switching circuit 21 is obtained by equating it with an inductor. Within the amplifier's operating frequency band F1, the capacitor switching circuit 21 is equivalent to an inductor with a larger inductance value than the second inductor 211 (which can be represented by Lout1), and acts as an output series inductor, together with the first inductor 22 and the first capacitor 23, to achieve output matching within the operating frequency band F1. When the output matching circuit 20 needs to switch to another operating frequency band F2, by changing the number of activated capacitor switching sub-circuits 212, the capacitor switching circuit 21 is equivalent to an inductor with a larger inductance value than the second inductor 211 (which can be represented by Lout2), and acts as an output series inductor, together with the first inductor 22 and the first capacitor 23, to achieve output matching within the operating frequency band F2.

[0040] In this embodiment, compared to Figure 1 Compared to the frequency band switching method using inductor 131 and switchable capacitors (capacitor 132 and switch 133) in the previous method, this disclosure uses a method of first connecting capacitor switching circuit 21 (second inductor 211 and switchable capacitor, the switchable capacitor being N capacitor switching sub-circuits 212) in series, and then cooperating with first inductor 22 and first capacitor 23 to perform frequency band switching. At this time, first inductor 22 is connected in parallel in output matching circuit 20, and first capacitor 23 is connected in series in output matching circuit 20. Compared to Figure 1 The matching method of inductor 131 and capacitor 134 in the output matching circuit 20 of this disclosure differs in the number and structure of the first inductor 22, first capacitor 23 and second inductor 211, thereby achieving higher gain and wider bandwidth; and, compared to Figure 1 The Q value and self-resonant frequency of the second inductor 211 in this disclosure are not sensitive to the overall performance of the inductor 131, which is very sensitive to the performance of the inductor 131. This switching method through the capacitor switching circuit 21 can minimize the loss of gain and bandwidth caused by frequency band switching, thereby achieving better performance.

[0041] In some embodiments, the capacitor switching circuit 21 is further configured to turn on M capacitor switching sub-circuits 212 in N capacitor switching sub-circuits 212 to determine the equivalent inductance value or equivalent capacitance value of the capacitor switching circuit 21.

[0042] It should be noted that, based on the determined values ​​of N and M, the number of capacitors connected to the output matching circuit 20 can be determined, and thus the equivalent inductance or equivalent capacitance value of the capacitor switching circuit 21 can be determined based on the inductance value of the second inductor 211 and the capacitance value corresponding to the capacitors connected to the output matching circuit 20.

[0043] In some embodiments, such as Figure 3As shown, the capacitor switching sub-circuit 212 may include a second capacitor 2121 and a switching circuit 2122 connected in series; the first end of the switching circuit 2122 serves as the first end of the capacitor switching sub-circuit 212, and the second end of the switching circuit 2122 is connected to the first end of the second capacitor 2121, with the second end of the second capacitor 2121 serving as the second end of the capacitor switching sub-circuit 212.

[0044] It should be noted that the switching circuit 2122 may include at least one switch, and there is no specific limitation on the number and structure of the switching circuit 2122. Exemplarily, the specific implementation of the embodiments of this disclosure will be described in detail with the example of the switching circuit 2122 including one switch.

[0045] Here, the second capacitor 2121 can be represented by Csw, and the switching circuit 2122 can be represented by Sw. The second capacitor 2121 and the switching circuit 2122 in the N capacitor switching sub-circuits 212 are represented by Csw1, Sw1, ..., CswN, SwN, respectively.

[0046] It should also be noted that the second capacitor 2121 in the N capacitor switching sub-circuits 212 can be set to different or the same capacitance value, and there is no specific limitation on this.

[0047] In this embodiment, by changing the on / off state of the switch circuit 2122, the number of capacitor switching sub-circuits 212 that are turned on can be changed, thereby changing the number of capacitors connected to the output matching circuit 20. Specifically, closing the switch circuit 2122 turns on the capacitor switching sub-circuit 212, connecting the corresponding second capacitor 2121 to the capacitor switching circuit 21; opening the switch circuit 2122 turns off the capacitor switching sub-circuit 212, preventing the corresponding second capacitor 2121 from being connected to the capacitor switching circuit 21.

[0048] When the amplifier is operating in a certain frequency band, the on / off state of N switches Sw is adjusted so that a certain switch Sw is closed and a certain switch Sw is open; when the output matching circuit 20 needs to switch to another operating frequency band, the switching is performed by changing the on / off state of different switches Sw.

[0049] For example, when N=3, closing switch Sw1 activates the first capacitor switching sub-circuit 212, connecting capacitor Csw1 to capacitor switching circuit 21; closing switches Sw1 and Sw2 activates the first and second capacitor switching sub-circuits 212, connecting capacitors Csw1 and Csw2 to capacitor switching circuit 21; and so on, without further explanation.

[0050] like Figure 4As shown, for example, among the N switches Sw, when switch Sw1 is closed and the other switches are open, the amplifier operates in frequency band F1, and the capacitor switching circuit 21 is equivalent to the inductor Lout1.

[0051] It should be noted that the capacitance value of the capacitor connected to the output matching circuit 20 is the sum of the capacitance values ​​of the second capacitor 2121 in all the conducting capacitor switching sub-circuits 212.

[0052] In some embodiments, the capacitor switching circuit 21 is further configured to determine the equivalent inductance value or equivalent capacitance value of the capacitor switching circuit 21 based on the inductance value of the second inductor 211 and the capacitance value of the second capacitor 2121 in the conducted capacitor switching sub-circuit 212.

[0053] In some embodiments, the capacitor switching circuit 21 is further configured to determine the resonant frequency based on the inductance value of the second inductor 211 and the capacitance value of the second capacitor 2121 in the conducted capacitor switching sub-circuit 212. The target frequency band includes the resonant frequency.

[0054] In this embodiment, after determining the resonant frequency, the target frequency band can be determined based on the resonant frequency, and then filtered.

[0055] It should be noted that the resonant frequency can be determined according to formula (1): (1) Where f0 represents the resonant frequency, L represents the inductance value, and C represents the capacitance value.

[0056] Here, L is the inductance value of the second inductor 211; C is the capacitance value determined based on the capacitance value of the second capacitor 2121 in the conducted capacitor switching sub-circuit 212, specifically the sum of the capacitance values ​​of the second capacitor 2121 in all conducted capacitor switching sub-circuits 212. For example, when Sw1 and Sw2 are closed, the first and second capacitor switching sub-circuits 212 are conducted, and Csw1 and Csw2 are connected in parallel, at which point C = Csw1 + Csw2.

[0057] based on Figure 4 The capacitor switching circuit 21 shown is described in the following text. Figure 5 It shows a schematic diagram of a filtering curve provided in an embodiment of this disclosure, where the horizontal axis represents frequency and the vertical axis represents gain. The target frequency band is as follows: Figure 5 As shown, point A represents the resonant frequency.

[0058] It should be noted that when the amplifier is operating in a certain frequency band, adjusting the on / off states of N switches Sw, so that specific switches Sw are closed and specific switches Sw are open, the capacitor switching circuit 21 can be considered as a resonant circuit in parallel with the second inductor 211 and the second capacitor 2121 in the conducted capacitor switching sub-circuit 212, which resonates at the frequency point where high-frequency suppression is required, to effectively filter the specific target frequency band. When the output matching circuit 20 needs to switch to another operating frequency band, it is switched by changing the on / off states of different switches Sw, so that the capacitor switching circuit 21 becomes a parallel resonant circuit resonating at the frequency point where out-of-band suppression is required in the current frequency band.

[0059] In this embodiment, since the Q value and self-resonant frequency of the second inductor 211 have little impact on performance, by configuring different states of switch Sw, the second inductor 211 can be flexibly matched with different capacitance values ​​of capacitor Csw, so that the capacitor switching circuit 21 becomes a resonant circuit (Tank) that resonates in the frequency band to be suppressed, thereby achieving the filtering effect of a specific frequency.

[0060] In some embodiments, the capacitor switching circuit 21 is further configured to determine the inductance value of the second inductor 211 and the capacitance value of the second capacitor 2121 in the conducted capacitor switching sub-circuit 212 as the equivalent inductance value of the capacitor switching circuit 21 when the operating frequency is less than the resonant frequency, so as to filter signals with frequencies greater than the operating frequency. Alternatively, it can be used to determine the inductance value of the second inductor 211 and the capacitance value of the second capacitor 2121 in the conducted capacitor switching sub-circuit 212 as the equivalent capacitance value of the capacitor switching circuit 21 when the operating frequency is greater than the resonant frequency, so as to filter signals that are less than the operating frequency. The operating frequency band includes the operating frequency.

[0061] It should be noted that when the operating frequency is lower than the resonant frequency, the capacitor switching circuit 21 is equivalent to an inductor and can perform high-frequency filtering; when the operating frequency is higher than the resonant frequency, the capacitor switching circuit 21 is equivalent to a capacitor and can perform low-frequency filtering.

[0062] In some embodiments, such as Figure 6 (As shown in the finely spaced dashed boxes) the first inductor 22 and the second inductor 211 are wound in the same coil.

[0063] It should be noted that two inductors wound in the same coil refers to integrating two independent inductor windings (coils) on the same physical frame or magnetic core with a specific spatial layout and electrical connection method, forming an inductor structure with a coupling relationship.

[0064] It should also be noted that this embodiment does not specifically limit the winding method; it can be any method. Figure 6 The shown U-shaped structure can be wound in other ways, as long as two inductors (first inductor 22 and second inductor 211) are achieved through the same coil.

[0065] In this embodiment, the first inductor 22 and the second inductor 211 are wound in the same coil, requiring only the space occupied by the first inductor 22 and the second inductor 211. Figure 1 The same layout area for inductor 131 and capacitor 134 can achieve the above functions, thereby further reducing the layout area and lowering costs.

[0066] This disclosure provides an output matching circuit 20 with frequency band switching and filtering functions. The output matching circuit 20 consists of a second inductor 211 connected in parallel with multiple switches Sw connected in series with capacitors Csw (i.e., capacitor switching sub-circuit 212), a first inductor 22, and a first capacitor 23. First, the matching method of the first inductor 22, the first capacitor 23, and the second inductor 211 has higher gain and wider bandwidth, and the Q value and self-resonant frequency of the second inductor 211 are not sensitive to the overall performance. This switching method can minimize the loss of gain and bandwidth caused by frequency band switching, thereby achieving better performance. Second, since the Q value and self-resonant frequency of the second inductor 211 have little impact on performance, by flexibly matching different capacitor values ​​of Csw and configuring different states of the switch Sw, the capacitor switching circuit 21 becomes a resonant circuit that resonates in the frequency band to be suppressed, and can also achieve filtering of specific frequencies. Furthermore, this disclosure reuses the capacitor switching circuit 21 used for frequency band switching, eliminating the need for additional switchable LC circuits to meet specific filtering requirements at different operating frequencies. This reduces the impact of adding additional matching devices on performance, while also reducing circuit complexity and layout area. Moreover, by winding the first inductor 22 and the second inductor 211 within the same coil, the layout area can be further reduced, thereby lowering costs.

[0067] In another embodiment of this disclosure, see Figure 7 It shows a schematic diagram of the structure of an amplifier provided in an embodiment of this disclosure. Figure 2 .like Figure 6 or Figure 7 As shown, amplifier 30 includes amplifier circuit 31 and output matching circuit 20, and amplifier circuit 31 is connected to output matching circuit 20.

[0068] It should be noted that amplifier 30 can be a power amplifier or a low-noise amplifier, without any specific limitation.

[0069] In some embodiments, as Figure 6 or Figure 7As shown, the amplifier circuit 31 may include a common-source transistor 311 and a common-gate transistor 312; the first terminal of the common-source transistor 311 is connected to the ground terminal, the second terminal of the common-source transistor 311 is connected to the first terminal of the common-gate transistor 312, the second terminal of the common-gate transistor 312 is connected to the output matching circuit 20 and is used to output the amplified signal, the control terminal of the common-source transistor 311 is used to receive the input signal, and the control terminal of the common-gate transistor 312 is used to receive the bias voltage.

[0070] It should be noted that the common-source transistor 311 is a transistor using a common-source connection, meaning the source is the common terminal for both input and output; the common-gate transistor 312 is a transistor using a common-gate connection, meaning the gate is the common terminal for both input and output. The common-source transistor 311 and the common-gate transistor 312 are connected to form a common-source, common-gate structure, enabling multiple transistors to perform cascaded amplification.

[0071] It should also be noted that the common-source transistor 311 and the common-gate transistor 312 can be NMOS transistors or P-type metal-oxide-semiconductor field-effect transistors (PMOS transistors), and there is no specific limitation in this regard. For example, the specific implementation of the embodiments of this disclosure will be described in detail with both the common-source transistor 311 and the common-gate transistor 312 being NMOS transistors.

[0072] Here, for the common-source transistor 311 and the common-gate transistor 312, their control terminal is typically the gate, one of the first terminal and the second terminal is the source, and the other is the drain. Specifically, the first terminal is the source, and the second terminal is the drain.

[0073] In some embodiments, such as Figure 6 or Figure 7 As shown, amplifier 30 may further include a switchable gain attenuation circuit 32, which is connected to output matching circuit 20; wherein: The switchable gain attenuation circuit 32 is used to receive the target signal and adjust the gain of the target signal.

[0074] It should be noted that the switchable gain attenuation circuit 32 can achieve dynamic gain adjustment.

[0075] In some embodiments, such as Figure 6 or Figure 7 As shown, amplifier 30 may also include input matching circuit 33, which is connected to amplifier circuit 31; The input matching circuit 33 is used to receive radio frequency signals, perform input impedance matching on the radio frequency signals, and obtain the input signal.

[0076] It should be noted that the input matching circuit 33 is specifically a switchable input matching circuit with filtering.

[0077] As for the amplifier 30, since it includes the aforementioned output matching circuit 20, it has at least the same advantages as the output matching circuit 20, namely, higher gain and wider bandwidth, which can achieve better performance; and can achieve filtering of specific frequencies; and can reduce circuit complexity, reduce layout area, and reduce cost.

[0078] In another embodiment of this disclosure, see [reference needed]. Figure 8 This illustrates a schematic diagram of the structure of an electronic device provided in an embodiment of this disclosure. For example... Figure 8 As shown, the electronic device 40 includes the aforementioned amplifier 30.

[0079] Here, electronic device 40 can be such as a computer, smartphone, tablet computer, laptop computer, PDA, personal digital assistant, navigation device, wearable device, etc., and this disclosure does not specifically limit it.

[0080] For details not disclosed in the embodiments of this disclosure, please refer to the description of the foregoing embodiments for understanding.

[0081] The above description is merely a preferred embodiment of this disclosure and is not intended to limit the scope of protection of this disclosure.

[0082] It should be noted that, in this disclosure, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0083] The sequence numbers of the embodiments disclosed above are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0084] The methods disclosed in the several method embodiments provided in this disclosure can be arbitrarily combined without conflict to obtain new method embodiments.

[0085] The features disclosed in the several product embodiments provided in this disclosure can be combined arbitrarily without conflict to obtain new product embodiments.

[0086] The features disclosed in the several method or device embodiments provided in this disclosure can be arbitrarily combined without conflict to obtain new method or device embodiments.

[0087] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure.

Claims

1. An output matching circuit, characterized in that, Applied to amplifiers; The output matching circuit is used to receive the amplified signal, determine the working frequency band among multiple frequency bands corresponding to the amplified signal, perform output impedance matching on the signal of the working frequency band, and output the target signal; the working frequency band is any one of the multiple frequency bands. The output matching circuit includes a capacitor switching circuit, a first inductor, and a first capacitor. The input terminal of the capacitor switching circuit is used to receive the amplified signal. The output terminal of the capacitor switching circuit is connected to the first terminal of the first inductor and the first terminal of the first capacitor, respectively. The second terminal of the first inductor is connected to the power supply terminal, and the second terminal of the first capacitor is used to output the target signal. Wherein: The capacitor switching circuit is used to filter signals in the target frequency band by adjusting the equivalent inductance or equivalent capacitance value of the capacitor switching circuit.

2. The output matching circuit according to claim 1, characterized in that, The capacitor switching circuit includes a second inductor connected in parallel and N capacitor switching sub-circuits. The first terminal of the second inductor is connected to the first terminals of each of the N capacitor switching sub-circuits and serves as the input terminal of the capacitor switching circuit. The second terminal of the second inductor is connected to the second terminals of each of the N capacitor switching sub-circuits and serves as the output terminal of the capacitor switching circuit. Wherein: The output matching circuit is further configured to activate M of the N capacitor switching sub-circuits and determine the operating frequency band among the plurality of frequency bands corresponding to the amplified signal; N is an integer greater than or equal to 1, and M is an integer greater than or equal to 1 and less than or equal to N.

3. The output matching circuit according to claim 2, characterized in that, The capacitor switching circuit is further configured to activate M of the N capacitor switching sub-circuits and determine the equivalent inductance or equivalent capacitance value of the capacitor switching circuit.

4. The output matching circuit according to claim 2, characterized in that, The capacitor switching sub-circuit includes a second capacitor and a switching circuit connected in series; the first end of the switching circuit serves as the first end of the capacitor switching sub-circuit, the second end of the switching circuit is connected to the first end of the second capacitor, and the second end of the second capacitor serves as the second end of the capacitor switching sub-circuit.

5. The output matching circuit according to claim 4, characterized in that, The capacitor switching circuit is further configured to determine the resonant frequency based on the inductance value of the second inductor and the capacitance value of the second capacitor in the activated capacitor switching sub-circuit. The target frequency band includes the resonant frequency.

6. The output matching circuit according to claim 5, characterized in that, The capacitor switching circuit is further configured to, when the operating frequency is less than the resonant frequency, determine the inductance value of the second inductor and the capacitance value of the second capacitor in the conducting capacitor switching sub-circuit as the equivalent inductance value of the capacitor switching circuit, and filter signals greater than the operating frequency. Alternatively, when the operating frequency is greater than the resonant frequency, the inductance value of the second inductor and the capacitance value of the second capacitor in the activated capacitor switching sub-circuit are determined as the equivalent capacitance value of the capacitor switching circuit, and the signal less than the operating frequency is filtered. The operating frequency band includes the operating frequency.

7. The output matching circuit according to claim 2, characterized in that, The first inductor and the second inductor are wound in the same coil.

8. An amplifier, characterized in that, The amplifier includes an amplification circuit and an output matching circuit as described in any one of claims 1 to 7, wherein the amplification circuit is connected to the output matching circuit.

9. The amplifier according to claim 8, characterized in that, The amplifier circuit includes a common-source transistor and a common-gate transistor; the first terminal of the common-source transistor is connected to the ground terminal, the second terminal of the common-source transistor is connected to the first terminal of the common-gate transistor, the second terminal of the common-gate transistor is connected to the output matching circuit and used to output an amplified signal, the control terminal of the common-source transistor is used to receive the input signal, and the control terminal of the common-gate transistor is used to receive the bias voltage.

10. An electronic device, characterized in that, The electronic device includes the amplifier as described in claim 8 or 9.

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