CN111383826B

CN111383826B - Inductance device and control method thereof

Info

Publication number: CN111383826B
Application number: CN201811623902.5A
Authority: CN
Inventors: 邓平援
Original assignee: Realtek Semiconductor Corp
Current assignee: Realtek Semiconductor Corp
Priority date: 2018-12-28
Filing date: 2018-12-28
Publication date: 2021-03-30
Anticipated expiration: 2038-12-28
Also published as: CN111383826A

Abstract

An inductance device comprises a splayed inductor and a ring coil, wherein the ring coil is arranged around the periphery of the splayed inductor. The splayed inductor comprises an input end and a central tap end, wherein the input end of the splayed inductor is positioned on the first side of the inductor device, and the central tap end is positioned on the second side of the inductor device. The annular coil comprises an input end and a grounding end, the input end of the annular coil is positioned on the first side of the inductance device, and the grounding end is positioned on the second side of the inductance device. The input end of the annular coil is coupled to the input end of the splayed inductor.

Description

Inductance device and control method thereof

Technical Field

The present disclosure relates to an electronic device and a method thereof, and more particularly, to an inductive device and a control method thereof.

Background

In a direct-up transmitter (direct-up transmitter), if the frequency of a Voltage Controlled Oscillator (VCO) is selected to be the same as the frequency of an even harmonic (even harmonic) of a Power Amplifier (PA), the VCO may be pulled by the PA (Pulling), which deteriorates the communication quality.

The conditions of the voltage-controlled oscillator affected by the power amplifier are divided into: "coupling between the inductance of the power amplifier and the inductance of the voltage-controlled oscillator" and "coupling between the power supply line of the power amplifier and the power supply line of the voltage-controlled oscillator". To solve the above problem, the frequency of the vco can be set at a non-integer frequency of the harmonic of the power amplifier, however, such an arrangement requires additional components, not only occupies the space of the whole device, but also is more likely to cause the rest of the interference condition. In addition, if the correction is performed by using an algorithm, the voltage controlled oscillator has more paths that may be affected by the power amplifier, which makes the algorithm difficult to implement.

Disclosure of Invention

This summary is provided to provide a simplified summary of the disclosure in order to provide a basic understanding to the reader. This summary is not an extensive overview of the disclosure and is intended to neither identify key/critical elements of the embodiments nor delineate the scope of the embodiments.

An object of the present invention is to provide a solution to the problems of the prior art, which will be described later.

To achieve the above object, one aspect of the present disclosure relates to an inductor device, which includes a figure eight inductor and a toroidal coil disposed around an outer periphery of the figure eight inductor. The splayed inductor comprises an input end and a central tap end, wherein the input end of the splayed inductor is positioned on the first side of the inductor device, and the central tap end is positioned on the second side of the inductor device. The annular coil comprises an input end and a grounding end, the input end of the annular coil is positioned on the first side of the inductance device, and the grounding end is positioned on the second side of the inductance device. The input end of the annular coil is coupled to the input end of the splayed inductor.

To achieve the above objects, another aspect of the present invention is a method for controlling an inductor device, the inductor device includes a figure eight inductor and a loop coil, the loop coil is disposed around the periphery of the figure eight inductor, wherein an input end of the figure eight inductor and an input end of the loop coil are both located on a first side of the inductor device, and a center tap end of the figure eight inductor and a ground end of the loop coil are both located on a second side of the inductor device, the method comprising: when the interference signal is fed from the central tap end, the interference signal forms currents on the splayed inductor and the annular coil respectively, wherein the current on the splayed inductor is opposite to the current on the annular coil.

Therefore, according to the technical content of the present disclosure, the inductance device and the control method thereof according to the embodiments of the present disclosure can change the inductance structure in a limited space, and can effectively reduce the coupling phenomenon between the vco and the power amplifier.

The basic spirit and other objects of the present invention, as well as the technical means and embodiments adopted by the present invention, will be readily understood by those skilled in the art after considering the following embodiments.

Drawings

In order to make the aforementioned and other objects, features, advantages and embodiments of the present invention comprehensible, the following description is made with reference to the accompanying drawings:

fig. 1 is a schematic diagram illustrating an inductive device according to an embodiment of the present disclosure.

Fig. 2 is a schematic diagram illustrating an operation of an inductive device according to an embodiment of the disclosure.

Fig. 3 is a schematic diagram illustrating an operation of an inductive device according to an embodiment of the present disclosure.

Fig. 4 is a schematic diagram illustrating an operation of an inductive device according to an embodiment of the present disclosure.

Fig. 5 is a flowchart illustrating a method for controlling an inductive device according to an embodiment of the present disclosure.

Fig. 6 is a schematic diagram illustrating experimental data of an inductive device according to an embodiment of the present disclosure.

In accordance with conventional practice, the various features and elements of the drawings are not drawn to scale in order to best illustrate the specific features and elements associated with the present disclosure. Moreover, the same or similar reference numbers are used throughout the different drawings to refer to similar components/features.

Description of the symbols:

100 inductance device

110 inductance device

111 input terminal

113 central tap end

120 toroidal coil

121 input terminal

123 ground terminal

500 method

510-520 steps

600 voltage controlled oscillator

Experimental curve C1-C3

I1-I4 Current

Ic bus current

In interference signal

Is surrounding current

T1-T2 transistor

Detailed Description

In order to make the disclosure more thorough and complete, illustrative descriptions are provided below for embodiments and specific examples of the disclosure; it is not intended to be exhaustive or to limit the invention to the precise form disclosed. The embodiments are intended to cover the features of the various embodiments as well as the method steps and sequences for constructing and operating the embodiments. However, other embodiments may be utilized to achieve the same or equivalent functions and step sequences.

Unless defined otherwise herein, 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 invention belongs. Furthermore, as used herein, the singular tense of a noun, unless otherwise conflicting with context, encompasses the plural form of that noun; the use of plural nouns also covers the singular form of such nouns.

Fig. 1 is a schematic diagram illustrating an inductive device 100 according to an embodiment of the present disclosure. As shown, the inductor device 100 includes a figure-of-eight inductor 110 and a toroid 120. In addition, the splayed inductor 110 includes an input end 111 and a central tap end 113, and the toroidal coil 120 includes an input end 121 and a ground end 123. The crossing portion (crossing) in the middle of the splayed inductor 110 may be implemented by a bridging structure, but the present disclosure is not limited thereto.

Structurally, the toroidal coil 120 is disposed around the periphery of the splayed inductor 110. However, the shape of the toroidal coil 120 shown in fig. 1 is not limited, and is only used to exemplarily illustrate one implementation manner, and in other implementation manners, the shape of the toroidal coil 120 may be disposed next to the splayed inductor 110 to have a gourd-like shape, or may be disposed in other suitable shapes according to actual requirements. It should be noted that the splayed inductor 110 and the toroidal coil 120 may be disposed on the same metal layer, however, the splayed inductor 110 and the toroidal coil 120 may be disposed on different metal layers as required.

Referring to fig. 1, the center tap 113 of the splayed inductor 110 and the ground terminal 123 of the toroidal coil 120 are both located on one side (i.e., the upper side) of the inductor device, and the input terminal 111 of the splayed inductor 110 and the input terminal 121 of the toroidal coil 120 are both located on the other side (i.e., the lower side) of the inductor device.

In one embodiment, the input end 121 of the toroidal coil 120 is coupled to the input end 111 of the inductor 110. For example, referring to fig. 2, an operation diagram of an inductive device 100 Is shown according to an embodiment of the present disclosure, which illustrates a differential mode (differential mode) signal of the inductive device 100, a Voltage Controlled Oscillator (VCO) 600 Is Controlled by a working current (not shown), an oscillation signal generated by the VCO 600 Is fed from an input end 111 of the wye-shaped inductor 110, and a surrounding current Is formed on the wye-shaped inductor 110. Wherein the oscillating signal Is a sine wave signal, and fig. 2 shows the flow direction of the oscillating signal of the first half cycle of the surrounding current Is.

Referring to fig. 2, since the current flowing into the node 111 Is equal to the current flowing out of the node, the surrounding current Is only flows around the splayed inductor 110 and does not flow through the toroidal coil 120. Based on the flowing direction of the surrounding current Is, a magnetic field penetrating out of the drawing Is formed above the splayed inductor 110, a magnetic field penetrating into the drawing Is formed below the splayed inductor 110, and the magnetic fields of the two are offset, so that an induced eddy (eddy current) Is not formed on the annular coil 120, and the quality factor (Q) of the splayed inductor 110 Is not reduced. In other embodiments, the input end 111 of the splayed inductor 110 includes a first end and a second end, and the surrounding current Is may be fed from the first end on the left side of the figure, flow around the splayed inductor 110, and then flow out from the second end on the right side of the figure.

In one embodiment, the distance between the splayed inductor 110 and the toroidal coil 120 is less than about 1 to 5 times the width of the inductor line of the splayed inductor 110. However, the present invention is not limited thereto, and the distance may be configured to be an appropriate multiple of the inductor line width according to the actual requirement.

In another embodiment, the input end 121 of the toroidal coil 120 is coupled to the input end 111 of the inductor 110. For example, referring to fig. 3, which is a schematic diagram illustrating an operation of the inductive device 100 according to an embodiment of the present disclosure, to illustrate a common mode signal of the inductive device 100, an input end 121 of the loop coil 120 is coupled to an input end 111 of the splayed inductor 110, and when an interference signal In is fed from the center tap 113, the interference signal In forms currents on the splayed inductor 110 and the loop coil 120, respectively. The interference signal In may be coupled from a Power Amplifier (PA) (not shown) into the splay inductor 110, but the present disclosure is not limited thereto. As shown In fig. 3, the current of the interference signal In flowing through the splayed inductor 110 is opposite to the current flowing through the toroidal coil 120. In one embodiment, the interference signal In includes a noise current (Inoise), but the disclosure is not limited thereto.

With reference to fig. 3, the interference signal In forms a first current I1 and a second current I2 on two opposite sides of the v-shaped inductor 110. As shown, the first current I1 and the second current I2 both flow from the second side (e.g., the upper side) to the first side (e.g., the lower side) of the inductive device 100. The first current I1 and the second current I2 are converged at the input end 111 of the v-shaped inductor 110 to form a bus current Ic. Then, the bus current Ic is fed from the input end 121 of the toroidal coil 120, and forms a third current I3 and a fourth current I4 on two opposite sides of the toroidal coil 120, and the third current I3 and the fourth current I4 both flow from the first side (e.g., the lower side) of the inductive device 100 to the ground terminal 123 on the second side (e.g., the upper side). Therefore, the currents I1 and I2 in the v-shaped inductor 110 flow from the second side to the first side of the inductor 100, and the currents I3 and I4 in the toroidal coil 120 flow from the second side to the first side of the inductor 100; therefore, the current flowing through the splayed inductor 110 is opposite to the current flowing through the toroidal coil 120, so that the magnetic field induced by the current flowing through the splayed inductor 110 and the magnetic field induced by the current flowing through the toroidal coil 120 cancel each other.

Fig. 4 is a schematic diagram illustrating an operation of the inductive device 100 according to an embodiment of the present disclosure. As shown in the figure, since the splay inductor 110 is used in the present application, the isolation between the power amplifier (not shown) and the vco 600 can be increased compared to the symmetrical inductor due to the magnetic field cancellation characteristic of the splay inductor 110. The coupling of the power line of the power amplifier to the power line of the vco 600 is a common mode signal for the vco 600. The signal of the power amplifier is a signal carrying modulation data, so if the vco 600 operates at the even harmonic frequency of the power amplifier, the modulation signal is a common mode interference signal In for the vco 600.

Referring to fig. 4, in the embodiment, the vco 600 includes cross-coupled transistors T1 and T2 and a capacitor, wherein the transistors T1 and T2 may be N-type metal oxide semiconductor field effect transistors (NMOS FETs), P-type metal oxide semiconductor field effect transistors (PMOS FETs), or complementary metal oxide semiconductor field effect transistors (CMOS FETs), which is not limited thereto. In one embodiment, the transistor T1 includes a first terminal coupled to the input terminal 111 of the splayed inductor 110, a first control terminal coupled to the input terminal 121 of the toroidal coil 120, and a second terminal. The transistor T2 includes a third terminal coupled to the input terminal 111 of the v-shaped inductor 110 and the first control terminal of the transistor T1, a second control terminal coupled to the first terminal of the transistor T1, and a fourth terminal coupled to the input terminal 121 of the toroidal coil 120. The capacitor is coupled between the first terminal of the transistor T1 and the third terminal of the transistor T2.

When the transistors T1 and T2 are turned on simultaneously, the waveform of the vco 600 passes through the zero-crossing point (zero-crossing point), which is the time when the vco 600 is most susceptible to noise interference. The present invention employs a single-turn splay inductor 110, and a ring-shaped coil 120 surrounding the common-mode signal flow path, so that the common-mode inductance value can be effectively reduced to L (1-m), where m is the coupling coefficient of the inductor. When the waveform of the vco 600 approaches the zero-crossing point, the vco is most easily interfered by the common mode signal, and at this time, the transistors T1 and T2 are turned on simultaneously, and the common mode interference signal In is equally divided into two paths and returned to the ground 123, so that the common mode inductance value L (1-m) can be reduced, and the pulling frequency (pulling) of the power amplifier of the vco is improved.

Fig. 5 is a flowchart illustrating a method 500 for controlling an inductive device according to an embodiment of the present disclosure. As shown, the method 500 for controlling an inductive device comprises the following steps:

step 510: when the interference signal is fed from the central tap end, the interference signal forms currents on the splayed inductor and the annular coil respectively, wherein the current on the splayed inductor is opposite to the current on the annular coil.

Step 520: when the oscillating signal is fed in from the input end of the splayed inductor, the oscillating signal forms a surrounding current on the splayed inductor.

For the easy understanding of the method 500 for controlling the inductive device, please refer to fig. 2, 3 and 5 together. In step 510, when the interference signal In is fed from the central tap 113, the interference signal In forms currents on the splayed inductor 110 and the toroidal coil 120, respectively, and the current on the splayed inductor 110 is opposite to the current on the toroidal coil 120. In one embodiment, the interference signal In includes a noise current (I)_noise) However, the present disclosure is not limited thereto.

In step 520, when the oscillating signal of the vco 600 Is fed from the input end 111 of the v-shaped inductor 110, the oscillating signal forms a surrounding current Is on the v-shaped inductor 110.

In one embodiment, the step of forming currents on the splayed inductor 110 and the toroidal coil 120 respectively according to the interference signal In includes: forming a first current I1 and a second current I2 on two opposite sides of the v-shaped inductor 110 according to the interference signal In, wherein the first current I1 and the second current I2 both flow from the second side to the first side of the inductor 100; and the first current I1 and the second current I2 are converged at the input end 111 of the splayed inductor 110 to form a bus current Ic.

In one embodiment, the step of forming currents on the splayed inductor 110 and the toroidal coil 120 respectively according to the interference signal In includes: the third current I3 and the fourth current I4 are formed on two opposite sides of the toroidal coil 120 according to the bus current Ic, wherein the third current I3 and the fourth current I4 both flow from the first side to the second side of the inductive device 100.

In one embodiment, the surrounding current Is only surrounds the inductor 110. In another embodiment, the input end 111 of the splayed inductor 110 comprises a first end and a second end, wherein the surrounding current Is fed into the first end and surrounds the splayed inductor 110, and Is discharged from the second end. In other embodiments, the interference signal In is a common mode signal and the oscillation signal is a differential mode signal.

Fig. 6 is a schematic diagram showing experimental data of an inductive device 100 according to an embodiment of the present disclosure. As shown in the figure, when the VCO 600 is not disturbed, the experimental curve is C1, and the phase noise (phase noise) is-90.39 dBc/Hz when the frequency is 100.0 kHz. When a high frequency noise is fed into the inductive device 100 without the present toroid 120, the experimental curve is C3, also taking 100.0kHz as an example, the phase noise is increased to-71.83 dBc/Hz. However, when the inductive device 100 having the toroidal coil 120 of the present invention is used, the experimental curve is C2, and similarly, when 100.0kHz is taken as an example, the phase noise is reduced to-86.07 dBc/Hz, so that the inductive device 100 having the toroidal coil 120 of the present invention can effectively reduce the interference to the vco 600.

According to the embodiments of the present invention, the following advantages can be obtained. The inductance device and the control method thereof can change the inductance structure in a limited space and effectively reduce the coupling phenomenon between the voltage-controlled oscillator and the power amplifier.

Although specific embodiments of the present disclosure have been described above, it should be understood that they have the ordinary skill in the art and various changes and modifications can be made therein without departing from the spirit and scope of the present disclosure, and therefore the scope of the present disclosure should be determined by the appended claims.

Claims

1. An inductive device, comprising:

an inductor shaped like a Chinese character 'ba', comprising:

an input terminal located at a first side of the inductive device; and

a central tap end located at a second side of the inductance device; and

a toroidal coil disposed around the periphery of the figure eight inductor, comprising:

an input terminal located at the first side of the inductance device; and

a ground terminal located at the second side of the inductor;

wherein the input end of the loop coil is coupled to the input end of the splayed inductor.

2. The inductive device of claim 1, wherein the input terminal of the toroidal coil is coupled to the input terminal of the inductor in a delta shape via an oscillator.

3. The inductive device of claim 2, wherein when an interference signal is fed from the central tap, the interference signal forms currents on the v-shaped inductor and the toroid, respectively, wherein the currents on the v-shaped inductor are opposite to the currents on the toroid.

4. The inductive device of claim 3, wherein the interference signal forms a first current and a second current on opposite sides of the inductance, wherein the first current and the second current both flow from the second side to the first side of the inductance, and the first current and the second current converge at the input end of the inductance to form a converging current, wherein the converging current is fed from the input end of the toroidal coil, and forms a third current and a fourth current on opposite sides of the toroidal coil, and both the third current and the fourth current flow from the first side to the second side of the inductance.

5. The inductive device of claim 3, wherein when a ringing signal is fed from the input terminal of the inductor, the ringing signal forms a circulating current on the inductor.

6. The inductive device of claim 5, wherein the circulating current flows around the inductance in a shape of Chinese character ba, wherein the input terminal of the inductance in a shape of Chinese character ba includes a first terminal and a second terminal, the circulating current is fed from the first terminal, flows around the inductance in a shape of Chinese character ba, and flows out from the second terminal of the input terminal.

7. The inductor device according to any one of claims 1 to 6, wherein the distance between the splayed inductor and the loop coil is less than 1 to 5 times the line width of the splayed inductor.

8. The inductive device of any of claims 5 to 6, wherein the interference signal is a common mode signal and the oscillating signal is a differential mode signal.

9. The inductor apparatus according to claim 1, wherein the figure-of-eight inductor and the toroid are disposed on a same metal layer, or the figure-of-eight inductor and the toroid are disposed on different metal layers.

10. A control method of an inductance device, wherein the inductance device comprises a splayed inductor and a loop coil, the loop coil is arranged around the periphery of the splayed inductor, wherein an input end of the splayed inductor and an input end of the loop coil are both positioned on a first side of the inductance device, and a central tap end of the splayed inductor and a ground end of the loop coil are both positioned on a second side of the inductance device, the control method comprising:

when an interference signal is fed from the central tap end, the interference signal forms currents on the splayed inductor and the loop coil respectively, wherein the currents on the splayed inductor are opposite to the currents on the loop coil.