Radio frequency devices and their inductors

Abstract

This application provides a radio frequency (RF) device and its inductor. The RF device includes a power amplifier circuit, a signal coupling circuit, an extraction circuit, and a harmonic filter circuit. The power amplifier circuit amplifies a differential signal to output a signal to be filtered. The signal coupling circuit includes a primary inductor and a secondary inductor. The signal coupling circuit receives the signal to be filtered through the primary inductor and outputs a single-ended signal from the secondary inductor. The extraction circuit has a center tap. The extraction circuit couples with the primary inductor and outputs a common-mode signal from the center tap. The harmonic filter circuit performs harmonic filtering on the single-ended signal based on the common-mode signal, so that the secondary inductor of the signal coupling circuit outputs a filtered signal.

Description

Technical Field

[0001] This invention relates to a communication transmission technology, and more particularly to a radio frequency device and its inductor. Background Technology

[0002] Radio frequency (RF) circuits generate harmonics such as second and third harmonics during operation, which can adversely affect other circuits. For example, in a WiFi 2.4 GHz application circuit, the second harmonic will generate a 4.8 GHz signal. Since 4.8 GHz is close to 5 GHz, this second harmonic will affect circuits operating in the 5 GHz band (such as WiFi 5 GHz applications).

[0003] The common way to address the impact of these harmonics on circuits is to install filters outside the radio frequency (RF) circuitry to remove them. However, filters installed outside the RF circuitry can affect the performance of the RF circuitry itself, occupy additional circuit space, and incur additional costs. Summary of the Invention

[0004] In view of the above, this invention provides a radio frequency (RF) device and its inductor. According to some embodiments, the RF device and its inductor of this invention can improve harmonic filtering efficiency, reduce the occupied circuit (or chip) space, and increase the symmetry of the circuit (or chip). For example, at least one of the aforementioned effects can be achieved by integrating the main components constituting the harmonic filter into some components already existing in the RF device.

[0005] According to some embodiments, the radio frequency device includes a power amplifier circuit, a signal coupling circuit, an extraction circuit, and a harmonic filter circuit. The power amplifier circuit amplifies a differential signal to output a signal to be filtered. The signal coupling circuit includes a primary inductor and a secondary inductor. The primary inductor receives the signal to be filtered, and the secondary inductor outputs a single-ended signal. The extraction circuit has a center tap. It couples with the primary inductor and outputs a common-mode signal from the center tap. The harmonic filter circuit performs harmonic filtering on the single-ended signal based on the common-mode signal, so that the secondary inductor of the signal coupling circuit outputs a filtered signal.

[0006] According to some embodiments, the inductor includes a wound first conductive layer pattern, a wound second conductive layer pattern, and a capacitor. The first conductive layer pattern forms a primary-side inductor and a secondary-side inductor of a signal coupling circuit. The signal coupling circuit is used to convert a signal to be filtered from the primary-side inductor into a single-ended signal from the secondary-side inductor. The second conductive layer pattern includes a first trace, a second trace, and a connector. One end of the first trace is coupled to a first node. One end of the second trace is coupled to a second node. The connector is coupled between the other ends of the first trace and the second trace and has a center tap. The first and second conductive layer patterns are arranged symmetrically with respect to a central axis, and the center tap is located on the central axis. The capacitor is coupled between the first node and the second node to form a resonant circuit with the second conductive layer pattern, which is a extraction circuit and a harmonic filtering circuit. The extraction circuit is used to couple with the primary-side inductor and output a common-mode signal from the center tap. Harmonic filtering circuits are used to perform harmonic filtering on single-ended signals based on common-mode signals, so that the secondary inductor of the signal coupling circuit outputs a filtered signal.

[0007] According to some embodiments, the inductor includes a wound first conductive layer pattern, a wound second conductive layer pattern, a first capacitor, and a wound third conductive layer pattern. The first conductive layer pattern forms a primary-side inductor and a secondary-side inductor of a signal coupling circuit. The signal coupling circuit is used to convert a signal to be filtered from the primary-side inductor into a single-ended signal from the secondary-side inductor. The second conductive layer pattern forms a resonant circuit of a harmonic filter circuit. The second conductive layer pattern includes a first trace, a second trace, and a connector. One end of the first trace is coupled to a first node. One end of the second trace is coupled to a second node. The connector is coupled between the other ends of the first trace and the second trace. The first capacitor is coupled between the first node and the second node. The third conductive layer pattern has a central tap. The two ends of the third conductive layer pattern are respectively coupled to a second capacitor and a third capacitor to form an extraction circuit. The first, second, and third conductive layer patterns are arranged symmetrically with respect to a central axis. The central tap is located on the central axis. The extraction circuit is used to couple with the primary-side inductor and output a common-mode signal from the center tap. The harmonic filtering circuit is used to perform harmonic filtering on the single-ended signal based on the common-mode signal, so that the secondary-side inductor of the signal coupling circuit outputs a filtered signal.

[0008] In summary, according to some embodiments of the present invention, the radio frequency device and its inductor cancel harmonics by using a signal with the same frequency as the harmonics but opposite in phase, thereby reducing the harmonics of the output signal without affecting the fundamental frequency of the output signal, and thus reducing the adverse effects of the radio frequency device and its inductor on other circuits (such as devices operating in other frequency bands). In some embodiments, since the harmonic filter for filtering harmonics is disposed within the radio frequency device and its inductor, some factors susceptible to external interference are reduced, thereby improving the effect of harmonic filtering, and the performance of the circuits in the radio frequency device itself can be avoided or additional costs can be avoided. Attached Figure Description

[0009] [ Figure 1 This is a block diagram of a two-radio frequency device based on some embodiments of this case.

[0010] [ Figure 2 [This is a block diagram of the radio frequency device in the first embodiment of this case.]

[0011] [ Figure 3 [This is a partial detailed circuit diagram of the radio frequency device in the first embodiment of this case.]

[0012] [ Figure 4 This is a block diagram of a two-radio frequency device based on some embodiments of this case.

[0013] [ Figure 5 This is a block diagram of the radio frequency device in the second embodiment of this case.

[0014] [ Figure 6 [This is a partial detailed circuit diagram of the radio frequency device in the second embodiment of this case.]

[0015] [ Figure 7 [This is a schematic diagram of the inductor device in the first embodiment of this case.]

[0016] [ Figure 8 [This is a schematic diagram of a portion of the structure of an inductor device according to some embodiments of this case.]

[0017] [ Figure 9 [This is a schematic diagram of the inductor device in the second embodiment of this case.]

[0018] [ Figure 10 [This is a schematic diagram of experimental data for a radio frequency device according to some embodiments of this case and a comparative example.] Detailed Implementation

[0019] The terms "first" and "second" as used herein are used to distinguish the elements referred to, not to order or limit the differences between the elements, nor to limit the scope of the invention. Furthermore, the terms "coupled" or "connected" refer to two or more elements making direct physical or electrical contact with each other, or making indirect physical or electrical contact with each other; for example, if the text describes a first device coupled to a second device, it means that the first device can be directly electrically connected to the second device, or indirectly electrically connected to the second device through other devices or connection means. In addition, the term "coupled" refers to inductive coupling.

[0020] Reference Figure 1 , Figure 1 This is a block diagram of two radio frequency devices 100 and 300 according to some embodiments of this invention. Radio frequency device 100 is coupled to antenna 200. When operating, radio frequency device 100 communicates (transmits signals) with another radio frequency device 300 via antenna 200. For example, a radio frequency transmitting circuit (not shown) in radio frequency device 100 outputs a signal (e.g., a radio frequency signal) via antenna 200, and a radio frequency receiving circuit (not shown) in radio frequency device 300 receives the signal from radio frequency device 100 via its coupled antenna 400.

[0021] Reference Figure 2 , Figure 2 This is a block diagram of the radio frequency device 100 according to the first embodiment of this case. The radio frequency device 100 includes a power amplifier circuit 101, a signal coupling circuit 102, an extraction circuit 103, and a harmonic filter circuit 104. The power amplifier circuit 101 is coupled to the signal coupling circuit 102. The harmonic filter circuit 104 is coupled to the extraction circuit 103.

[0022] In some embodiments, the radio frequency device 100 further includes a processing circuit 105. The processing circuit 105 processes data from the radio frequency device 100 and converts data intended for communication transmission to an external location (such as the radio frequency device 300) into differential signals Vi+ and Vi-. The processing circuit 105 may be an embedded controller, a central processing unit, a microprocessor, an application-specific integrated circuit, or a system-on-a-chip (SoC) or other computing circuitry. In some embodiments, a power amplifier circuit 101 is coupled to the processing circuit 105 to obtain the differential signals Vi+ and Vi- from the processing circuit 105.

[0023] Reference Figure 2 and Figure 3 . Figure 3This is a partial detailed circuit diagram of the radio frequency device 100 according to the first embodiment of this case. The power amplifier circuit 101 is used to amplify the differential signals Vi+ and Vi- to output a filterable signal Vo+ and Vo-. In some embodiments, the power amplifier circuit 101 includes at least one pair of common-source transistors (e.g., Figure 3 The common source transistors M1 to M6 are shown. Figure 3 Although three pairs of common-source transistors M1 to M6 are used as an example here, it is not limited to only three pairs. The number of common-source transistor pairs can be less than three pairs or more than three pairs, depending on the desired gain of the signal. Here, we will use three pairs of common-source transistors M1 to M6 as an example. For example, common-source transistors M1 to M6 can be N-type metal-oxide-semiconductor transistors (MODS) and are connected in series (e.g., the sources of common-source transistors M3 and M4 are coupled to the drains of common-source transistors M1 and M2, and the drains of common-source transistors M3 and M4 are coupled to the sources of common-source transistors M5 and M6). The drains of common-source transistors M5 and M6 are coupled to signal coupling circuit 102 (two input terminals 813 and 814 of signal coupling circuit 102). The sources of common-source transistors M1 and M2 are both coupled to a ground potential GND, and their gates are respectively coupled to two output terminals of processing circuit 105 to obtain differential signals Vi+ and Vi-. After the common-source transistors M1 to M6 amplify the differential signals Vi+ and Vi-, the filtered signals Vo+ and Vo- are output from the drains of common-source transistors M5 and M6 to signal coupling circuit 102. In some embodiments, the common-source transistors M3 to M6 can be configured based on the bias voltage V of their gates. G1 V G2 To adjust the magnitude of the gain it provides (e.g., bias potential V). G1 V G2 A higher bias voltage (V) provides greater gain, and vice versa. G1 V G2 It can be obtained from the self-processing circuit 105.

[0024] The signal coupling circuit 102 includes a primary-side inductor 1021 and a secondary-side inductor 1022. The signal coupling circuit 102 can be a balancer (balanced to unbalanced). The signal coupling circuit 102 is used to convert the signals Vo+ and Vo- received by the primary-side inductor 1021 into a single-ended signal V output from the secondary-side inductor 1022. SSpecifically, one end of the secondary inductor 1022 (hereinafter referred to as the secondary ground terminal 812) is coupled to the ground potential GND, and the other end (hereinafter referred to as the output terminal 811) is coupled to the antenna 200. The two ends of the primary inductor 1021 (i.e., the two input terminals 813 and 814 of the signal coupling circuit 102) are respectively coupled to the two output terminals of the power amplifier circuit 101 (i.e., the drains of the common-source transistors M5 and M6) to receive the signals Vo+ and Vo- to be filtered. The primary inductor 1021 is coupled to the secondary inductor 1022 to convert the signals Vo+ and Vo- to be filtered into a single-ended signal V. S .

[0025] Extraction circuit 103 has a center-tapped 1031. Extraction circuit 103 is used to couple with primary-side inductor 1021 and output a common-mode signal V from center-tapped 1031. U Specifically, the extraction circuit 103 is coupled to the primary-side inductor 1021 to obtain the signals Vo+ and Vo- to be filtered, and based on the signals Vo+ and Vo- to be filtered, the common-mode signal V of the power amplifier circuit 101 is output from the center tap 1031. U The common-mode signal V U The voltage value can be obtained by adding the signals Vo+ and Vo- to be filtered and then dividing by two. In some embodiments, the common-mode signal V U The signal to be filtered can mainly consist of harmonics in the signals Vo+ and Vo-. These harmonics can be harmonics of the fundamental frequency (the main operating frequency of the RF device 100), such as the second or third harmonic. For example, if the fundamental frequency is 2.4 GHz, then the second harmonic is 4.8 GHz, and the third harmonic is 7.2 GHz. For instance, the extraction circuit 103 has a low-frequency filtering function (e.g., implemented using a capacitor) and performs low-frequency filtering on the obtained signals Vo+ and Vo- (e.g., suppressing the fundamental frequency wave in the signals Vo+ and Vo-) to retain harmonics with frequencies higher than the fundamental frequency (fundamental frequency wave), thus forming a common-mode signal V. U .

[0026] Harmonic filter circuit 104 is used to filter based on common mode signal V U The single-ended signal V on the secondary inductor 1022 S A harmonic filter is performed so that the secondary inductor 1022 of the signal coupling circuit 102 outputs a filtered signal V through the antenna 200. F (i.e., the aforementioned radio frequency signal) is transmitted to the outside of the radio frequency device 100 (such as the radio frequency device 300). The harmonic filter circuit 104 is coupled to the center tap 1031 of the extraction circuit 103 to obtain the common-mode signal V. UThe harmonic filter circuit 104 can be a high-frequency filter circuit or a band-block filter circuit, and the harmonic filtering can be either high-frequency filtering or band-block filtering. Because the single-ended signal V... S The signal is obtained by conversion through signal coupling circuit 102, therefore the signals to be filtered Vo+ and Vo- are related to the single-ended signal V. S They have similar fundamental frequencies and similar harmonics. The harmonic filtering circuit 104 performs harmonic filtering to preserve the single-ended signal V. S The fundamental frequency wave in the signal is used to suppress the single-ended signal V. S The second and third harmonics of the fundamental frequency wave are used to form the filtered signal V. F For example, the harmonic filter circuit 104 is based on the common-mode signal V. U Generates a single-ended signal V S A harmonic voltage signal with opposite phase to the harmonic (e.g., a single-ended signal V) S If the phase of a harmonic is 180 degrees, then the phase of the harmonic voltage signal is zero degrees; or, for a single-ended signal V... S If the phase of the harmonic is zero degrees, then the phase of the harmonic voltage signal is 180 degrees. Therefore, the harmonic filter circuit 104 couples the harmonic voltage signal to the single-ended signal V. S To eliminate single-ended signal V S The harmonics in the signal form the filtered signal V. F In some embodiments, the harmonic voltage signal can be compared with a single-ended signal V. S The harmonics in the middle have the same voltage level and the same frequency.

[0027] Reference Figure 4 , Figure 4 This is a block diagram of two radio frequency devices 100 and 500 according to some embodiments of this invention. Taking the main operating frequency of radio frequency device 100 as 2.4 GHz and the main operating frequency of radio frequency device 500 as 5 GHz as an example, since radio frequency devices 100 and 500 operate in different frequency bands, they can share the same antenna 200 via a duplexer 510. If the signal (e.g., radio frequency signal) output by radio frequency device 100 through antenna 200 is not subjected to harmonic filtering, it will interfere with the signal generated by radio frequency device 500 during operation. For example, the second harmonic generated by radio frequency device 100 is 4.8 GHz. Since 4.8 GHz is close to 5 GHz, if this second harmonic is not filtered out, it will interfere with the operation of radio frequency device 500. Therefore, according to the above embodiments of this invention, radio frequency device 100 solves this problem by effectively filtering out the harmonics it generates (e.g., the filtered signal V output by radio frequency device 100). F Because harmonics have been filtered out, the operation of the radio frequency device 500 will not be affected.

[0028] In some embodiments, such as Figure 2 As shown, the harmonic filter circuit 104 includes a first amplifier circuit 1041, a second amplifier circuit 1042, and a resonant circuit 1043. The first amplifier circuit 1041 and the second amplifier circuit 1042 are respectively coupled between the center tap 1031 of the extraction circuit 103 and the resonant circuit 1043. The first amplifier circuit 1041 is used to amplify the common-mode signal V at a first phase. U To output a first amplified signal V A1 The second amplifier circuit 1042 is used to amplify the common-mode signal V in a second phase. U To output a second amplified signal V A2 The resonant circuit 1043 is used to control the common-mode signal V. U Based on the first amplified signal V in the first phase A1 Coupled single-ended signal V S and in the common-mode signal V U Based on the second amplified signal V in the second phase A2 Coupled single-ended signal V S For single-ended signal V S Perform harmonic filtering.

[0029] Continuing, in order to eliminate harmonics of different phases, the common-mode signal V of different phases is amplified by using different paths and components on those paths. U This generates a harmonic current that is opposite in phase to the harmonic. For example, due to a single-ended signal V... S Since it is an AC signal, in some cases, the single-ended signal V... S The phase of the harmonics in the signal is zero degrees, at which point the common-mode signal V... U The phase (first phase) is zero degrees, and the common-mode signal V at this time is amplified by the first amplifier circuit 1041 located on the first filter path 10. U To output a first amplified signal V that is opposite in phase to the first phase. A1 (i.e., a harmonic current signal with a phase of 180 degrees), the resonant circuit 1043 is based on the first amplified signal V A1 This generates a harmonic voltage signal with the opposite phase to the first harmonic (i.e., a harmonic voltage with a phase of 180 degrees), and couples this harmonic voltage to a single-ended signal V. S This eliminates the single-ended signal V. S The zero-degree phase harmonics in the signal. Similarly, in other cases, the single-ended signal V... S The phase of the harmonics in the signal is 180 degrees, at which point the common-mode signal V... U The phase (second phase) is 180 degrees. The resonant circuit 1043 obtains a second amplified signal V, which is opposite to the second phase, through the second amplification circuit 1042 located on the second filter path 20.A2 (i.e., a harmonic current signal with a phase of zero degrees), and based on the second amplified signal V A2 This generates a harmonic voltage with the opposite phase to the second phase (i.e., a harmonic voltage signal with zero phase) to eliminate the single-ended signal V. S The harmonics of the 180-degree phase. In some embodiments, the first phase and the second phase are out of phase.

[0030] In some embodiments, such as Figure 3 As shown, the first amplifier circuit 1041 and the second amplifier circuit 1042 may each include a common-source transistor M7 and M8. The drains of the common-source transistors M7 and M8 are respectively coupled to different terminals of the resonant circuit 1043, and the gates of the common-source transistors M7 and M8 are coupled to the center tap 1031 of the extraction circuit 103 to obtain the common-mode signal V under the first phase. U and the common-mode signal V in the second phase U In the common-mode signal V U In the first phase, the common-source transistor M7 amplifies the common-mode signal V at this time. U The first amplified signal V is output through its drain. A1 To the resonant circuit 1043. In the common-mode signal V U In the second phase, the common-source transistor M8 amplifies the common-mode signal V at this time. U To output a second amplified signal V via its drain A2 To the resonant circuit 1043. The common-source transistors M7 and M8 can be N-type metal-oxide-semiconductor transistors.

[0031] In some embodiments, such as Figure 3 As shown, the resonant circuit 1043 can be an inductor-capacitor parallel resonant circuit (LC parallel resonant circuit). For example, the resonant circuit 1043 includes at least one inductor L3 and a capacitor connected in parallel with the inductor L3 (hereinafter referred to as the first capacitor C1) to respond to a single-ended signal V. S Harmonic filtering is performed. Specifically, the values ​​of inductor L3 and first capacitor C1 are configured so that the resonant frequency formed by them is similar to that of the single-ended signal V. S The harmonics have the same frequency to suppress the first amplified signal V. A1 and the second amplified signal V A2 Other non-harmonic frequencies of the wave, thus enabling the coupling of the harmonic voltage signal to the single-ended signal V. S Afterwards, only the single-ended signal V is canceled out. S Harmonics without affecting the single-ended signal V S The fundamental frequency wave. In some embodiments, the resonant circuit 1043 can be used for second harmonic filtering, that is, the aforementioned resonant frequency can be twice the fundamental frequency.

[0032] In some embodiments, such as Figure 2 As shown, the harmonic filter circuit 104 further includes a switching circuit 1044. The switching circuit 1044 is coupled between the first amplifier circuit 1041, the second amplifier circuit 1042, and the resonant circuit 1043. The switching circuit 1044 is used to switch the harmonic filter paths (first filter path 10 and second filter path 20) of the radio frequency device 100. The first filter path 10 is shown as a single-point link in the diagram. The second filter path 20 is shown as a two-point link in the diagram. In the common-mode signal V... U In the first phase, the switching circuit 1044 connects the coupling between the first amplification circuit 1041 and the resonant circuit 1043 to form the first filter path 10, and causes the resonant circuit 1043 to output the first amplified signal V. A1 Perform harmonic filtering. In the common-mode signal V... U In the second phase, the switching circuit 1044 activates the coupling between the second amplifier circuit 1042 and the resonant circuit 1043 to form the second filter path 20, and causes the resonant circuit 1043 to output the second amplified signal V. A2 Perform harmonic filtering.

[0033] In some embodiments, such as Figure 3 As shown, the switching circuit 1044 can be implemented using transistors. For example, the switching circuit 1044 includes two pairs of common-source transistors M9 to M12. The first pair of common-source transistors M9 and M10 controls whether the coupling between the first amplifier circuit 1041 and the resonant circuit 1043 is turned on, thereby determining whether the first filter path 10 is formed. The second pair of common-source transistors M11 and M12 controls whether the coupling between the second amplifier circuit 1042 and the resonant circuit 1043 is turned on, thereby determining whether the second filter path 20 is formed. For example, the gates of the common-source transistors M9 and M10 are coupled to a bias potential V. G3 The gates of common-source transistors M11 and M12 are coupled to a bias voltage V. G4 The drains of common-source transistors M10 and M12 are commonly coupled to a system potential V. DD The source of common-source transistor M9 is coupled to the first amplifier circuit 1041, the source of common-source transistor M11 is coupled to the second amplifier circuit 1042, the source of common-source transistor M10 and the drain of common-source transistor M11 are coupled to one end of resonant circuit 1043, and the source of common-source transistor M12 and the drain of common-source transistor M9 are coupled to the other end of resonant circuit 1043. Thus, when common-source transistors M9 and M10 are turned on, a first filter path 10 is formed, allowing resonant circuit 1043 to obtain the first amplified signal V from the first amplifier circuit 1041. A1When the common-source transistors M11 and M12 are turned on, a second filter path 20 is formed, allowing the resonant circuit 1043 to obtain the second amplified signal V from the second amplifier circuit 1042. A2 The system potential V DD It can provide power to the components within the radio frequency device 100. The common-source transistors M9 to M12 can be N-type metal-oxide-semiconductor transistors.

[0034] In the aforementioned embodiment, the bias potential V G3 V G4 They can be at opposite levels, causing one pair of common-source transistors M9 to M12 to be on while the other pair is off. For example, in the common-mode signal V... U In the first phase, the bias potential V G3 For high voltage levels, common-source transistors M9 and M10 are turned on, while the bias potential V is at this time. G4 To achieve a low threshold, the common-source transistors M11 and M12 are de-conducted; conversely (e.g., in the common-mode signal V...). U In the second phase, common source transistors M9 and M10 are not conducting, while common source transistors M11 and M12 are conducting.

[0035] In some embodiments, such as Figure 2 As shown, the harmonic filter circuit 104 further includes two matching circuits 1045 and 1046. Matching circuit 1045 is coupled between the center tap 1031 and the first amplifier circuit 1041, and matching circuit 1046 is coupled between the center tap 1031 and the second amplifier circuit 1042. Matching circuit 1045 is located in the first filter path 10, and matching circuit 1046 is located in the second filter path 20. Matching circuits 1045 and 1046 are used to respectively handle the common-mode signal V under the first phase. U The common-mode signal V in the second phase U Phase and impedance matching is performed to output a phase- and impedance-matched common-mode signal V. U The signal is transmitted to the first amplifier circuit 1041 and the second amplifier circuit 1042. Thereby, the common-mode signal V, after phase and impedance matching, is... U It can be matched with the first amplifier circuit 1041, the second amplifier circuit 1042 and other components in the radio frequency device 100 (such as the resonant circuit 1043).

[0036] Reference Figure 2 and Figure 3In the first embodiment, the extraction circuit 103 is an inductor L1. The two ends of the inductor L1 are coupled to the resonant circuit 1043 of the harmonic filter circuit 104 to form a single loop with the resonant circuit 1043 (e.g., inductor L1 is connected in parallel with the resonant circuit 1043, or inductor L1 is connected in series with the resonant circuit 1043). This reduces the chance of signal interference from other components in the radio frequency device 100. Since the inductor L1 and the resonant circuit 1043 form a single loop, the inductor L1 and the resonant circuit 1043 form a resonant frequency, based on which the resonant circuit 1043 performs harmonic filtering. In some embodiments, the resonant circuit 1043 can perform second harmonic filtering, so the resonant frequency formed by the inductor L1 and the resonant circuit 1043 can be the single-ended signal V. S The frequency of the fundamental wave (fundamental frequency) is twice that of the primary inductor 1021, while the fundamental frequency (the main operating frequency of the RF device 100) corresponds to the single-ended signal V. S The fundamental frequency of the inductor is twice the fundamental frequency of the primary inductor 1021. In some embodiments, the inductor L1 and the resonant circuit 1043 form an inductor-capacitor parallel resonant circuit (e.g., inductor L1, inductor L3, and first capacitor C1 are connected in parallel). In some embodiments, the center tap 1031 of the extraction circuit 103 is located on the inductor L1 (specifically, at the center point of the inductor L1).

[0037] Reference Figure 5 and Figure 6 . Figure 5 This is a block diagram of the radio frequency device 100 in the second embodiment of this case. Figure 6 This is a partial detailed circuit diagram of the radio frequency device 100 according to the second embodiment of this case. In some embodiments, in addition to obtaining the signals Vo+ and Vo- to be filtered through the primary inductor 1021 of the coupling signal coupling circuit 102, the extraction circuit 103 can also obtain the signals Vo+ and Vo- to be filtered through coupling. For example, as Figure 5 and Figure 6 As shown, the difference from the first embodiment is that in the second embodiment, the two ends of the extraction circuit 103 are also coupled to the two ends of the primary inductor 1021 of the signal coupling circuit 102 and the two output ends of the power amplifier circuit 101, respectively, so as to obtain the filtered signals Vo+ and Vo- from the primary inductor 1021 or the power amplifier circuit 101.

[0038] In some embodiments, the extraction circuit 103, in addition to outputting the common-mode signal V UIn addition, it can also provide harmonic filtering function, and the frequency of the harmonics it filters can be different from the frequency of the harmonics filtered by the harmonic filter circuit 104. For example, a resonant frequency of the extraction circuit 103 is three times a fundamental frequency (the main operating frequency of the RF device 100) of the primary inductor 1021. The extraction circuit 103 uses the characteristics of its passive components and resonant frequency to perform third harmonic filtering on the signals Vo+ and Vo- to be filtered, thereby making the filtered signal V F (or a single-ended signal V) S It does not have a third harmonic. In this case, the harmonic filter circuit 104 can be used for single-ended signal V. S Perform second harmonic filtering to make the filtered signal V F It does not have second harmonics. Therefore, the radio frequency device 100 can simultaneously filter out multiple harmonics of different frequencies, so that the output signal contains only the fundamental frequency (or has very few harmonics). For example, such as Figure 5 and Figure 6 As shown, the difference from the first embodiment is that in the second embodiment, the extraction circuit 103 includes two capacitors (taking a second capacitor C2 and a third capacitor C3 as an example) and an inductor L2. The inductor L2 is coupled between the second capacitor C2 and the third capacitor C3. By configuring the values ​​of the inductor L2, the second capacitor C2, and the third capacitor C3, the aforementioned resonant frequency is formed. That is, the resonant frequency formed by the inductor L2, the second capacitor C2, and the third capacitor C3 can be three times the fundamental frequency of the primary inductor 1021. In some embodiments, the center tap 1031 of the extraction circuit 103 is located on the inductor L2 (specifically, at the center point of the inductor L2).

[0039] Reference Figure 2 and Figure 7 , Figure 7 This is a schematic diagram of the inductor device 600 according to the first embodiment of this case. Wherein, Figure 7 The inductor 600 shown corresponds to Figure 2 The signal coupling circuit 102, extraction circuit 103, and harmonic filtering circuit 104 are shown. The inductor device 600 includes a wound first conductive layer pattern 610, a wound second conductive layer pattern 620, and a capacitor (hereinafter referred to as the first capacitor 630). The first conductive layer pattern 610 forms the primary-side inductor 1021 and the secondary-side inductor 1022 of the signal coupling circuit 102. Specifically, the first conductive layer pattern 610 has a first end 611, a second end 612, a third end 613, a fourth end 614, and a fifth end 615, respectively corresponding to… Figure 2 The signal coupling circuit 102 shown includes its output terminal 811, secondary side ground terminal 812, two input terminals 813 and 814, and system potential V. DDThe feed point is 830.

[0040] The second conductive layer pattern 620 includes a first trace 621, a second trace 622, and a connector 623. One end of the first trace 621 is coupled to a first node N1. One end of the second trace 622 is coupled to a second node N2. The connector 623 is coupled between the other ends of the first trace 621 and the second trace 622, and has a central tap 6230. The central tap 6230 corresponds to... Figure 2 The central tap 1031 is shown. A first capacitor 630 is coupled between a first node N1 and a second node N2 to form a resonant circuit 1043 with the second conductive layer pattern 620, comprising the extraction circuit 103 and the harmonic filtering circuit 104. The first capacitor 630, the first node N1, and the second node N2 respectively correspond to… Figure 2 The first capacitor C1 and its two connecting terminals 815 and 816 are shown, and the second conductive layer pattern 620 corresponds to... Figure 2 The inductors L1 and L3 are shown. The first conductive layer pattern 610 and the second conductive layer pattern 620 are arranged symmetrically with respect to a central axis CX1, and the central tap 6230 is located on the central axis CX1. This increases the structural symmetry of the inductor device 600. In some embodiments, the second conductive layer pattern 620 is located outside (or on the periphery) of the first conductive layer pattern 610.

[0041] In some embodiments, such as Figure 7 As shown, the first trace 621 includes a first sub-trace 6210 and a second sub-trace 6213. One end of the first sub-trace 6210 (hereinafter referred to as the second end of the first sub-trace 6210) and one end of the second sub-trace 6213 (hereinafter referred to as the second end of the second sub-trace 6213) are coupled to the first node N1. The second trace 622 includes a third sub-trace 6220 and a fourth sub-trace 6223. One end of the fourth sub-trace 6223 (hereinafter referred to as the second end of the fourth sub-trace 6223) and one end of the third sub-trace 6220 (hereinafter referred to as the second end of the third sub-trace 6220) are coupled to the second node N2.

[0042] Reference Figure 8 , Figure 8This is a schematic diagram of a portion of the structure 30 of an inductor device 600 according to some embodiments of this invention. A first sub-trace 6210 includes a plurality of first coils 6211. A second sub-trace 6213 includes a plurality of second coils 6212. The first coils 6211 and second coils 6212 are arranged alternately. For example, the first coil 6211 is wound from the first sub-trace 6210, and the second coil 6212 is wound from the second sub-trace 6213. The first coils 6211 and second coils 6212 are arranged alternately, for example, in the order of "first coil 6211, second coil 6212, first coil 6211, second coil 6212… etc." (See combined reference) Figure 7 The first coil 6211 and the second coil 6212 are located in the partial structure 30, which is located outside (or periphery) of the first conductive layer pattern 610.

[0043] Similarly, refer to Figure 7 The upper right corner of the structure 40 includes a third sub-line 6220 comprising a plurality of third coils 6221, and a fourth sub-line 6223 comprising a plurality of fourth coils 6222. The coupling and arrangement of the third coils 6221 and the fourth coils 6222 are the same as those of the first coil 6211 and the second coil 6212, and will not be described in detail here for the sake of brevity in this specification.

[0044] It should be noted that, in Figure 7 The lower left and lower right corners of the inductor 600 have structures similar to partial structures 30 and partial structures 40. Similarly, their coupling method and arrangement are the same as those of the first coil 6211 and the second coil 6212. For the sake of brevity, these will not be described in detail here.

[0045] In some embodiments, connector 623 is coupled between the other end of the first sub-trace 6210 (hereinafter referred to as the first end of the first sub-trace 6210) and the other end of the third sub-trace 6220 (hereinafter referred to as the first end of the third sub-trace 6220). The other ends of the second sub-trace 6213 (hereinafter referred to as the first end 624 of the second sub-trace 6213) and the other ends of the fourth sub-trace 6223 (hereinafter referred to as the first end 625 of the fourth sub-trace 6223) are respectively coupled to a first amplifier circuit 1041 and a second amplifier circuit 1042 of the harmonic filter circuit 104. That is, the first end 624 of the second sub-trace 6213 corresponds to the first amplified signal V of the first amplifier circuit 1041. A1 The feed point 824, and the first end 625 of the fourth sub-trace 6223 correspond to the second amplified signal V of the second amplifier circuit 1042. A2 The feed point is 825.

[0046] For example, the first sub-route 6210, the second sub-route 6213, the third sub-route 6220, and the fourth sub-route 6223 all include a first end and a second end. Figure 7 As shown, the second end of the first sub-trace 6210 (as shown below) and the second end of the second sub-trace 6213 (as shown below) are coupled to the first node N1. The second end of the third sub-trace 6220 (as shown below) and the second end of the fourth sub-trace 6223 (as shown below) are coupled to the second node N2. The first ends of the first sub-trace 6210 and the third sub-trace 6220 are located at the upper side of the figure. The first end of the first sub-trace 6210 is coupled to one end of the connector 623, while the other end of the connector 623 is coupled to the first end of the third sub-trace 6220. The first end of the first sub-trace 6210 winds around to the left side of the figure. Then, the first sub-trace 6210 winds downwards along the left side. After winding to the lower left side of the figure, it winds around to the first node N1 at the lower side of the figure. The second end of the first sub-trace 6210 is finally coupled to the first node N1. Similarly, the first end of the third sub-router 6220 goes around to the right side of the diagram. Then, the third sub-router 6220 goes down along the right side. After going around to the lower right side of the diagram, it goes around to the second node N2 at the lower side of the diagram. The second end of the third sub-router 6220 is finally coupled to the second node N2.

[0047] At the first node N1, the second end of the second sub-trace 6213 is coupled to the first node N1. The second end of the second sub-trace 6213 winds to the left side of the diagram. Then, the second sub-trace 6213 winds upward along the left side. After reaching the upper left side of the diagram, it winds towards the upper connector 623 in the diagram, reaching the first end 624 of the second sub-trace 6213 located at the upper side of the diagram, to couple with the first amplifier circuit 1041. Similarly, at the second node N2, the second end of the fourth sub-trace 6223 is coupled to the second node N2. The second end of the fourth sub-trace 6223 winds to the right side of the diagram. Then, the fourth sub-trace 6223 winds upward along the right side. After reaching the upper right side of the diagram, it winds towards the upper connector 623 in the diagram, reaching the first end 625 of the fourth sub-trace 6223 located at the upper side of the diagram, to couple with the second amplifier circuit 1042. As can be seen from the above structural configuration, the first sub-trace 6210, the second sub-trace 6213, the third sub-trace 6220 and the fourth sub-trace 6223 form a folded inductor architecture.

[0048] Reference Figure 5 and Figure 9 , Figure 9 This is a schematic diagram of the inductor device 600 according to the second embodiment of this case. Wherein, Figure 9 The inductor 600 shown corresponds to Figure 5The signal coupling circuit 102, extraction circuit 103, and harmonic filtering circuit 104 are shown. The difference from the first embodiment is that in the second embodiment, the inductor 600 further includes a wound third conductive layer pattern 640. The second conductive layer pattern 620 forms the resonant circuit 1043 of the harmonic filtering circuit 104. The two ends of the third conductive layer pattern 640 are respectively coupled to a second capacitor 650 and a third capacitor 660 to form the extraction circuit 103. Specifically, the third conductive layer pattern 640 is coupled between the second capacitor 650 and the third capacitor 660. A central tap 6230 is disposed on the third conductive layer pattern 640. The central tap 6230 corresponds to... Figure 5 The central tap 1031 is shown. The second capacitor 650 and the third capacitor 660 respectively correspond to... Figure 5 The second capacitor C2 and the third capacitor C3 shown correspond to the third conductive layer pattern 640. Figure 5 The inductor L2 shown corresponds to the second conductive layer pattern 620. Figure 5 The inductor L3 shown. The first conductive layer pattern 610, the second conductive layer pattern 620, and the third conductive layer pattern 640 are all arranged symmetrically with respect to the central axis CX1. This increases the structural symmetry of the inductor device 600. In some embodiments, the third conductive layer pattern 640 is located inside the first conductive layer pattern 610. This reduces the required circuit placement space.

[0049] In some embodiments, the inductor 600 is disposed on a substrate (not shown), the substrate may have a multilayer structure, and at least one of the first conductive layer pattern 610, the second conductive layer pattern 620 and the third conductive layer pattern 640 may be disposed across different layers of the multilayer structure to form a signal coupling circuit 102, an extraction circuit 103 and a harmonic filtering circuit 104.

[0050] Reference Figure 10 , Figure 10This diagram illustrates experimental data for a radio frequency (RF) device 100 according to some embodiments of this invention and a comparative example. In the comparative example, harmonic filtering was not performed on the output signal (e.g., the RF signal). The experimental curves for power response parameters (e.g., the power response between the input power and output power of the RF device 100) are E1, E2, and E3. The input power of the RF device 100 is the input power of the power amplifier circuit 101, and the output power of the RF device 100 is the output power of the signal coupling circuit 102. Curve E1 represents the fundamental frequency of the output signal (e.g., the RF signal) of the RF device 100 according to some embodiments of this invention and the comparative example; curve E2 represents the power response of the harmonics of the output signal of the comparative example; and curve E3 represents the power response of the harmonics of the output signal of the RF device 100 according to some embodiments of this invention. It can be seen that the harmonic power shown in the embodiments of this invention is lower than that of the harmonic power in the comparative example. Therefore, if the RF device 100 of the embodiments of this invention is used, the harmonics of the output signal can be reduced.

[0051] In summary, according to some embodiments of the present invention, the radio frequency device and its inductor cancel harmonics by using a signal with the same frequency as the harmonics but opposite in phase, thereby reducing the harmonics of the output signal without affecting the fundamental frequency of the output signal, and thus reducing the adverse effects of the radio frequency device and its inductor on other circuits (such as devices operating in other frequency bands). In some embodiments, since the harmonic filter for filtering harmonics is disposed within the radio frequency device and its inductor, some factors susceptible to external interference are reduced, thereby improving the effect of harmonic filtering, and the performance of the circuits in the radio frequency device itself can be avoided or additional costs can be avoided.

[0052] [Symbol Explanation]

[0053] 100, 300, 500: Radio frequency devices

[0054] 101: Power Amplifier Circuit

[0055] Vi+, Vi-: Differential signals

[0056] Vo+, Vo-: Signals to be filtered

[0057] M1~M6: Common source transistor

[0058] V G1 V G2 Bias potential

[0059] GND: Grounding potential

[0060] 102: Signal coupling circuit

[0061] 1021: Primary inductor

[0062] 1022: Secondary inductor

[0063] V S Single-ended signal

[0064] V F Filtered signal

[0065] 813, 814: Input terminals

[0066] 811: Output terminal

[0067] 812: Secondary side grounding terminal

[0068] 103: Extraction Circuit

[0069] 1031: Central Government Withdrawal

[0070] V U Common-mode signal

[0071] L1, L2: Inductors

[0072] C2: Second capacitor

[0073] C3: Third capacitor

[0074] 104: Harmonic Filtering Circuit

[0075] 1041: First Amplifier Circuit

[0076] V A1 First amplified signal

[0077] M7: Common Source Transistor

[0078] 1042: Second amplifier circuit

[0079] V A2 Second amplified signal

[0080] M8: Common Source Transistor

[0081] 1043: Resonant Circuit

[0082] L3: Inductor

[0083] C1: First capacitor

[0084] 815, 816: Connecting ends

[0085] 824, 825: Feed points

[0086] V DD System potential

[0087] 830: Feed point

[0088] 1044: Switching Circuit

[0089] M9~M12: Common source transistor

[0090] V G3 V G4 Bias potential

[0091] 1045, 1046: Matching circuit

[0092] 105: Processing Circuit

[0093] 10: First filtering path

[0094] 20: Second filtering path

[0095] 200, 400: Antenna

[0096] 510: Duplexer

[0097] 600: Inductor

[0098] 610: Pattern of the first conductive layer

[0099] 611: First end

[0100] 612: Second end

[0101] 613: Third end

[0102] 614: Fourth end

[0103] 615: Fifth end

[0104] 620: Pattern of the second conductive layer

[0105] 621: First route

[0106] 6210: First sub-line

[0107] 6211: First coil

[0108] 6213: Second sub-line

[0109] 6212: Second coil

[0110] 622: Second route

[0111] 6220: Third sub-line

[0112] 6221: Third coil

[0113] 6223: Fourth sub-line

[0114] 6222: Fourth coil

[0115] 623: Connector

[0116] 6230: Central government withdrawal

[0117] 624: The first end of the second sub-line

[0118] 625: The first end of the fourth sub-line

[0119] 30, 40: Partial Structure

[0120] CX1: Central axis

[0121] 630: First capacitor

[0122] N1: First node

[0123] N2: Second node

[0124] 640: Pattern of the third conductive layer

[0125] 650: Second capacitor

[0126] 660: Third capacitor

[0127] E1~E3: Curves.

Claims

1. A radio frequency device, comprising: A power amplifier circuit is used to amplify a differential signal to output a signal to be filtered. A signal coupling circuit includes a primary inductor and a secondary inductor. The signal coupling circuit is used to receive the signal to be filtered through the primary inductor and output a single-ended signal through the secondary inductor. An extraction circuit having a center tap, the extraction circuit being coupled to the primary-side inductor and outputting a common-mode signal from the center tap; and A harmonic filter circuit is used to perform a harmonic filter on the single-ended signal based on the common-mode signal, so that the secondary inductor of the signal coupling circuit outputs a filtered signal.

2. The radio frequency device according to claim 1, wherein the harmonic filtering circuit comprises: A first amplifier circuit is used to amplify the common-mode signal at a first phase to output a first amplified signal; A second amplifier circuit is used to amplify the common-mode signal at a second phase to output a second amplified signal; and A resonant circuit is used to couple the single-ended signal with the first amplified signal in the first phase of the common-mode signal, and to couple the single-ended signal with the second amplified signal in the second phase of the common-mode signal, so as to perform harmonic filtering on the single-ended signal.

3. The radio frequency device according to claim 2, wherein the first phase and the second phase are out of phase with each other.

4. The radio frequency device according to claim 2, wherein the harmonic filtering circuit further includes a switching circuit coupled between the first amplifier circuit, the second amplifier circuit and the resonant circuit, so as to conduct the coupling between the first amplifier circuit and the resonant circuit when the common-mode signal is in the first phase, and to conduct the coupling between the second amplifier circuit and the resonant circuit when the common-mode signal is in the second phase.

5. The radio frequency device according to claim 2, wherein the harmonic filtering circuit further comprises two matching circuits, respectively coupled between the center tap and the first amplifier circuit and between the center tap and the second amplifier circuit, for performing phase and impedance matching on the common-mode signal in the first phase and the common-mode signal in the second phase, respectively, so as to output the phase and impedance matched common-mode signal to the first amplifier circuit and the second amplifier circuit.

6. The radio frequency device according to claim 2, wherein the extraction circuit is an inductor, the two ends of the inductor are coupled to the resonant circuit, and the resonant frequency formed by the inductor and the resonant circuit is twice the fundamental frequency of the primary inductor.

7. The radio frequency device according to claim 6, wherein the inductor and the resonant circuit form an inductor-capacitor parallel resonant circuit.

8. The radio frequency device of claim 1, wherein a resonant frequency of the extraction circuit is three times a fundamental frequency of the primary inductor.

9. The radio frequency device according to claim 8, wherein the two ends of the extraction circuit are coupled to the primary-side inductor, the extraction circuit includes two capacitors and an inductor, the inductor is coupled between the two capacitors, and the resonant frequency formed by the inductor and the two capacitors is three times the fundamental frequency of the primary-side inductor.

10. An inductor device comprising: A first conductive layer pattern is wound to form a primary-side inductor and a secondary-side inductor of a signal coupling circuit, wherein the signal coupling circuit is used to convert a signal to be filtered from the primary-side inductor into a single-ended signal from the secondary-side inductor. A wound second conductive layer pattern, comprising: A first trace, one end of which is coupled to a first node; A second trace, one end of which is coupled to a second node; and A connecting member is coupled between the other end of the first trace and the other end of the second trace and has a center tap, wherein The first conductive layer pattern and the second conductive layer pattern are arranged symmetrically with respect to a central axis, and the central tap is located on the central axis. as well as A capacitor is coupled between the first node and the second node to form a resonant circuit with the second conductive layer pattern, which includes an extraction circuit and a harmonic filtering circuit. The extraction circuit is used to couple with the primary inductor and output a common-mode signal from the center tap. The harmonic filtering circuit is used to perform harmonic filtering on the single-ended signal based on the common-mode signal, so that the secondary inductor of the signal coupling circuit outputs a filtered signal.

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