CN110783079B

CN110783079B - Inductance structure

Info

Publication number: CN110783079B
Application number: CN201911090064.4A
Authority: CN
Inventors: 康斯坦丁·库兹涅佐夫; 袁晟; 丹尼尔·拉尔斯顿
Original assignee: Spreadtrum Communications Shanghai Co Ltd
Current assignee: Spreadtrum Communications Shanghai Co Ltd
Priority date: 2019-11-08
Filing date: 2019-11-08
Publication date: 2021-11-02
Anticipated expiration: 2039-11-08
Also published as: CN110783079A

Abstract

An inductive structure, comprising: the even rings are distributed on the same plane around the central point, each ring is formed by winding a conducting wire and is provided with a starting end and a tail end; each ring and the adjacent ring share the same wire segment, and the current directions of the two adjacent rings are opposite; the even number of rings includes first partial rings each having the same current direction and second partial rings each having the same current direction, and the current direction of each of the first partial rings is opposite to the current direction of each of the second partial rings. The scheme provided by the invention can maximize the inductance isolation and reduce the electromagnetic coupling between the VCO resonators.

Description

Inductance structure

Technical Field

The invention relates to the technical field of circuits, in particular to an inductor structure.

Background

Recent advances in wireless communication technology allow entire Radio Frequency (RF) transceivers to be implemented on a single chip. However, implementing the entire RF transceiver on a single chip presents a number of challenges.

For example, in a Wideband Code Division Multiple Access (W-CDMA) transceiver, a single chip solution requires two RF Voltage-Controlled oscillators (VCOs) to operate on one chip simultaneously. Such an arrangement can produce unwanted interaction between the two VCOs due to various different types of mutual coupling mechanisms, which can result in spurious receiver responses at unwanted frequencies in the transmit spectrum. The primary mutual coupling mechanism is typically the fundamental Electromagnetic (EM) coupling between resonators, i.e., between large inductor structures in the VCO.

There are a number of techniques in the prior art for reducing the EM mutual coupling between VCOs due to inductance. However, these schemes typically require additional circuitry (e.g., power dividers, mixers, etc.) to implement, which increases current consumption.

Disclosure of Invention

The invention solves the technical problem of how to effectively improve the inductance isolation and reduce the electromagnetic coupling between VCO resonators.

To solve the above technical problem, an embodiment of the present invention provides an inductor structure, including: the even rings are distributed on the same plane around the central point, each ring is formed by winding a conducting wire and is provided with a starting end and a tail end; each ring and the adjacent ring share the same wire segment, and the current directions of the two adjacent rings are opposite; the even number of rings includes first partial rings each having the same current direction and second partial rings each having the same current direction, and the current direction of each of the first partial rings is opposite to the current direction of each of the second partial rings.

Optionally, in the plane, an outer contour of the figure formed by the even number of rings is an axisymmetric figure.

Optionally, the total area enclosed by each ring in the first partial ring is equal to the total area enclosed by each ring in the second partial ring.

Alternatively, the starting ends of the wires of each loop are coupled to each other, and the ends of the wires of each loop are coupled to each other.

Optionally, the number of the even number of rings is 4.

Optionally, the 4 rings are a first ring, a second ring, a third ring and a fourth ring in sequence in a clockwise direction on the plane, the first partial ring includes the first ring and the third ring, and the second partial ring includes the second ring and the fourth ring.

Optionally, the sum of the areas enclosed by the first ring and the third ring is equal to the sum of the areas enclosed by the second ring and the fourth ring.

Optionally, the first ring, the second ring, the third ring and the fourth ring enclose equal areas.

Optionally, the first ring and the second ring share a first conductor segment, the first ring and the fourth ring share a second conductor segment, the third ring and the second ring share a third conductor segment, and the third ring and the fourth ring share a fourth conductor segment.

Optionally, the current inflow end of each of the first ring, the second ring, the third ring and the fourth ring is coupled, and the current outflow end of each of the first ring, the second ring, the third ring and the fourth ring is coupled.

Compared with the prior art, the technical scheme of the embodiment of the invention has the following beneficial effects:

an embodiment of the present invention provides an inductor structure, including: the even rings are distributed on the same plane around the central point, each ring is formed by winding a conducting wire and is provided with a starting end and a tail end; each ring and the adjacent ring share the same wire segment, and the current directions of the two adjacent rings are opposite; the even number of rings includes first partial rings each having the same current direction and second partial rings each having the same current direction, and the current direction of each of the first partial rings is opposite to the current direction of each of the second partial rings. Compared with the prior art, the inductance structure can maximize inductance isolation and reduce electromagnetic coupling between VCO resonators. Specifically, the inductance structure according to the embodiment of the present invention can achieve the effect of minimizing the generated magnetic field without being interfered by the magnetic field from the external source on the basis of not depending on the symmetrical design, and minimize the interference of the inductance structure to other devices or electronic circuits. Further, each loop has a beginning and an end of a conductive line such that the inductive structure can be connected to a plurality of active devices. Further, the current direction of each ring in the first partial ring is opposite to that of each ring in the second partial ring, so that the inductance structure can counteract forward and reverse magnetic fields, inductance isolation is achieved to the maximum extent, and electromagnetic coupling between VCO resonators and between the VCO internal inductance structure and other devices is reduced.

Further, the total area enclosed by each ring in the first partial ring is equal to the total area enclosed by each ring in the second partial ring. Therefore, the inductance structure can basically counteract the forward and reverse magnetic fields.

Drawings

Fig. 1 is a schematic diagram of a first inductor structure according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a second inductor structure according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a third inductor structure according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a fourth inductor structure according to an embodiment of the invention.

Detailed Description

As noted in the background, existing inductive designs for reducing electromagnetic coupling between VCO resonators need to be implemented by means of additional circuitry, increasing the current consumption of the VCO.

On the other hand, in some prior art schemes, the magnetic field of the inductance structure itself is cancelled by adopting a symmetrical design. For example, by designing the coils to be symmetrical about a horizontal and/or vertical axis, the magnetic fields generated by the inductive structure may be made to tend to cancel.

However, the inductor structure based on the symmetric design has strict requirements on the shape, so that the placeable position of the inductor structure in the VCO is limited, which is not favorable for the miniaturization design of the whole structure of the VCO.

The inductance structure can maximize inductance isolation and reduce electromagnetic coupling between the VCO resonators. Those skilled in the art understand that the same conductive line is not necessarily the same continuous conductive line, but may be connected by a connecting line due to layer crossing or line crossing in the layout.

Specifically, the inductance structure according to the embodiment of the present invention can achieve the effect of minimizing the generated magnetic field without being interfered by the magnetic field from the external source on the basis of not depending on the symmetrical design, and minimize the interference of the inductance structure to other devices or electronic circuits.

Further, each loop has a beginning and an end of a conductive line such that the inductive structure can be connected to a plurality of active devices. Further, the current direction of each ring in the first partial ring is opposite to that of each ring in the second partial ring, so that the inductance structure can counteract forward and reverse magnetic fields, inductance isolation is achieved to the maximum extent, and electromagnetic coupling between VCO resonators and between the VCO internal inductance structure and other devices is reduced.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

Fig. 1 is a schematic diagram of a first inductor structure according to an embodiment of the present invention. The inductance structure described in this embodiment can be applied to a VCO resonator.

Specifically, referring to fig. 1, the inductance structure 100 may include: an even number of rings 110, the even number of rings 110 being distributed on the same plane around the center point a, each ring 110 being formed by winding a conductive wire and having a start end and an end. Wherein, the plane can be a plane formed by an x axis and a y axis in the figure; the center point a may be a center point of an outer contour of the figure formed by the even number of rings 110.

The even number of rings 110 distributed on the same plane around the center point a may mean that the even number of rings 110 are distributed on the same plane around the center point a in a top view state, that is, viewed in a direction perpendicular to a plane formed by the x axis and the y axis.

For example, referring to fig. 1, the even number of rings 110 may be 4 in number. In a plan view, the 4 rings 110 are a first ring 111, a second ring 112, a third ring 113, and a fourth ring 114 in this order in a clockwise direction on the plane. In a top view, the outer contour of the inductor structure 100 is rectangular, and the first ring 111, the second ring 112, the third ring 113, and the fourth ring 114 form a closed-loop structure around a central point a of the rectangle.

More specifically, each ring 110 shares the same wire segment with an adjacent ring 110, and the current flow direction of the adjacent two rings 110 is opposite. Wherein the wire segment belongs to a part of a wire; the current direction is a direction in which a current flows in the ring in a plan view.

For example, referring to fig. 1, the first and

second rings

111, 112 share a first wire segment s1, the first and

fourth rings

111, 114 share a second wire segment s2, the third and

second rings

113, 112 share a third wire segment s3, and the third and

fourth rings

113, 114 share a fourth wire segment s 4.

Further, the first ring 111 may be wound from a wire having a start 111a and a tail 111 b. The first lead wire segment s1 is the first lead wire segment, and the second lead wire segment s2 is the last lead wire segment.

The second loop 112 may be made of a wire wound with a beginning 112a and an end 112 b. The first lead wire segment s1 is the first lead wire segment, and the third lead wire segment s3 is the last lead wire segment.

The third loop 113 may be formed by winding a wire having a start end 113a and a tail end 113 b. The first lead wire segment is the fourth lead wire segment s4, and the last lead wire segment is the third lead wire segment s 3.

The fourth ring 114 may be formed from a wire wound with a beginning 114a and an end 114 b. The first lead wire segment is the fourth lead wire segment s4, and the last lead wire segment is the second lead wire segment s 2.

Thus, in the embodiment shown in fig. 1, the starting end 111a of the conductive wire of the first loop 111 and the starting end 112a of the conductive wire of the second loop 112 may be the same terminal; the end 111b of the wire of the first ring 111 and the end 114b of the wire of the fourth ring 114 may be the same terminal; the end 112b of the wire of the second loop 112 and the end 113b of the wire of the third loop 113 may be the same terminal; the starting end 113a of the wire of the third ring 113 and the starting end 114a of the wire of the fourth ring 114 may be the same terminal.

In a specific implementation, the common conductor segment may be the entire adjacent edge of two adjacent rings 110.

Assuming that the starting end of the wire is a current inflow end, and the end of the wire is a current outflow end, according to the current direction shown by the arrow in fig. 1, in a top view, the current direction of the first ring 111 is a counterclockwise direction, the current direction of the second ring 112 is a clockwise direction, the current direction of the third ring 113 is a counterclockwise direction, and the current direction of the fourth ring 114 is a clockwise direction.

Accordingly, the directions of the magnetic fluxes generated by the second ring 112 and the fourth ring 114 are both directions (indicated by "-" in the figure) perpendicular to the plane and extending into the plane; the directions of the magnetic fluxes generated by the first ring 111 and the third ring 113 are both directions perpendicular to and extending out of the plane (indicated by "+" in the drawing).

It can be seen that, since the conducting wire segment shared by two adjacent loops 110 is the end segment or the initial segment of the conducting wire, the current directions of two adjacent loops 110 are opposite, so that the forward and reverse magnetic fields of the inductance structure 100 itself can be cancelled out.

Further, the even number of rings 110 may include a first partial ring 120 and a second partial ring 130, a current direction of each ring 110 in the first partial ring 120 is the same, a current direction of each ring 110 in the second partial ring 130 is the same, and a current direction of each ring 110 in the first partial ring 120 is opposite to a current direction of each ring 110 in the second partial ring 130.

For example, referring to fig. 1, the first partial ring 120 may include the first ring 111 and the third ring 113, and the second partial ring 130 may include the second ring 112 and the fourth ring 114.

Further, in the embodiment shown in fig. 1, the direction of the magnetic flux generated by the first partial ring 120 is "+", and the direction of the magnetic flux generated by the second partial ring 130 is "-". When the total magnetic flux generated by the first partial ring 120 and the second partial ring 130 have the same value and opposite directions, the magnetic field interference between the even number of rings 110 can be substantially cancelled without being affected by the shape or symmetry of the inductance structure 100. Wherein the total magnetic flux is the integral of the magnetic field over the area enclosed by the ring 110.

Accordingly, by designing a plurality of coils not having axial symmetry as a requirement, the inductance structure 100 of the present embodiment can substantially cancel the current induced on the coils by the external magnetic field.

In a specific implementation, the inductance structure 100 may connect a plurality of active devices, and the magnetic field generated by the even number of loops 110 and the plurality of active devices can be cancelled away from the VCO circuit by the structural design of the inductance structure 100, so as to avoid the VCO resonator from being interfered by the magnetic field.

For example, referring to fig. 1, the beginning 111a and the end 111b of the conductive line of the first ring 111 may be coupled to a first active device 140; the beginning 112a and the end 112b of the conductive line of the second ring 112 may be coupled to a second active device 150; the start 113a and end 113b of the conductive line of the third loop 113 may be coupled to a third active device 160; the beginning 114a and the end 114b of the conductive line of the fourth ring 114 may be coupled to a fourth active device 170.

In a specific implementation, the outer contour of the figure formed by the even number of rings 110 may be an axisymmetric figure in the plane. In practical applications, the axisymmetric pattern may be substantially symmetrical to meet the requirements of the manufacturing process. For example, in order to reduce the sharp corners, some smoothing process may be performed at the corners of each ring 110, so that the outline of the graph formed by the even number of rings 110 is slightly non-axisymmetric; for example, in manufacturing, the outer contour of the pattern formed by the even number of rings 110 may be non-axisymmetric in a slight portion due to process errors. But these do not affect the general axial symmetry of the outer contour.

For example, referring to fig. 1, the pattern of 4 rings 110 may be rectangular and symmetrical left and right along the illustrated symmetry axis α and up and down along the illustrated symmetry axis β.

In a specific implementation, the total area enclosed by each ring 110 in the first partial ring 120 is equal to the total area enclosed by each ring 110 in the second partial ring 130. This makes it possible to substantially cancel the forward and reverse magnetic fields in the inductance structure 100 itself.

Based on the above description of the manufacturing process, the total area may be substantially equal, or the deviation between the total area enclosed by the rings 110 in the first partial ring 120 and the total area enclosed by the rings 110 in the second partial ring 130 may be within a preset error range. For example, the predetermined error range may be up to 1000-.

For example, referring to fig. 1, the sum of the areas surrounded by the first ring 111 and the third ring 113, respectively, and the sum of the areas surrounded by the second ring 112 and the fourth ring 114, respectively, may be equal. Thus, the magnitude of the total magnetic flux generated by the ring 110 having the clockwise direction of current flow can be substantially equal to the magnitude of the total magnetic flux generated by the ring 110 having the counterclockwise direction of current flow.

Further, the opposite direction of the current causes the magnetic flux to be opposite, so that the magnetic field generated by the ring 110 with the clockwise direction of the current and the magnetic field generated by the ring 110 with the counterclockwise direction of the current can substantially cancel each other, so that the magnetic field generated by the first partial ring 120 and the magnetic field generated by the second partial ring 130 substantially cancel each other. Therefore, the inductor structure 100 has substantially no magnetic field leakage to the outside, and the inductor isolation is realized.

In a particular implementation, the area enclosed by each ring 110 of the even number of rings 110 may be equal. For example, referring to fig. 1, the areas enclosed by the first ring 111, the second ring 112, the third ring 113, and the fourth ring 114 may be equal.

Therefore, by adopting the scheme of the embodiment, the inductance isolation can be maximized, and the electromagnetic coupling between the VCO resonators can be reduced.

Specifically, the inductance structure 100 according to the embodiment of the present invention can achieve the effects of not being interfered by a magnetic field from an external source and minimizing a generated magnetic field on the basis of not depending on a symmetrical design, and minimize interference of the inductance structure 100 on other devices or electronic circuits.

Further, each loop 110 has a beginning and an end of a conductive line, such that the inductive structure 100 can be connected to a plurality of active devices.

Further, by setting the current direction of each loop 110 in the first partial loop 120 to be opposite to the current direction of each loop 110 in the second partial loop 130, the inductance structure 100 itself achieves the cancellation of forward and reverse magnetic fields, thereby maximally achieving inductance isolation and reducing electromagnetic coupling between VCO resonators and between the VCO internal inductance structure and other devices.

Fig. 2 is a schematic diagram of a second inductor structure according to an embodiment of the present invention. In the following detailed explanation, descriptions about matters and features common to the embodiment shown in fig. 1 are omitted, and only different points are explained. In particular, the same operational effects produced by the same structures are not mentioned one by one for each embodiment. Like parts are designated by like reference numerals throughout the several views.

Only the differences between the inductor structure 200 shown in fig. 2 and the inductor structure 100 shown in fig. 1 will be described here.

In the present embodiment, the difference from the above-mentioned embodiment shown in fig. 1 is mainly that the starting ends of the conductive wires of each ring 110 may be coupled to each other, and the ends of the conductive wires of each ring 110 may be coupled to each other. Wherein the coupling is equipotential coupling.

For example, referring to fig. 2, the current inflow end of each ring 110 of the first ring 111, the second ring 112, the third ring 113 and the fourth ring 114 is coupled, and the current outflow end of each ring 110 of the first ring 111, the second ring 112, the third ring 113 and the fourth ring 114 is coupled.

In other words, on the basis that the start end 111a of the wire of the first ring 111 and the start end 112a of the wire of the second ring 112 share the same terminal, the end 111b of the wire of the first ring 111 and the end 114b of the wire of the fourth ring 114 share the same terminal, the end 112b of the wire of the second ring 112 and the end 113b of the wire of the third ring 113 share the same terminal, and the start end 113a of the wire of the third ring 113 and the start end 114a of the wire of the fourth ring 114 share the same terminal, the start end 111a of the wire of the first ring 111 and the start end 113a of the wire of the third ring 113 may be coupled at an equal potential, and the end 112b of the wire of the second ring 112 and the end 111b of the wire of the first ring 111 may be coupled at an equal potential.

Further, the starting end 111a of the conductive line of the first ring 111 and the end 111b of the conductive line of the first ring 111 may be coupled to the active device 240.

Thus, an even number of loops 110 may be formed in parallel with the inductive structure 200, and the inductive structure 200 may be coupled to an active device 240.

Fig. 3 is a schematic diagram of a third inductor structure according to an embodiment of the present invention. Only the differences between the inductor structure 300 shown in fig. 3 and the inductor structure 100 shown in fig. 1 will be described here.

In this embodiment, the difference from the inductance structure 100 shown in fig. 1 is mainly that the areas of one or more of the first ring 111, the second ring 112, the third ring 113 and the fourth ring 114 may not be equal.

For example, referring to fig. 3, on the basis of ensuring that the sum of the area surrounded by the first ring 311 and the area surrounded by the third ring 313 is equal to the sum of the area surrounded by the second ring 312 and the area surrounded by the fourth ring 314, the area surrounded by the first ring 311 may be smaller than the area surrounded by the second ring 312, and the area surrounded by the fourth ring 314 may be smaller than the area surrounded by the third ring 313.

In a specific implementation, for each ring 110 of the even number of rings 110, there is at least one other ring 110 of the even number of rings 110 that is the same shape and area as the ring 110. For example, the first ring 311 and the fourth ring 314 may have the same shape and area, and the third ring 313 and the second ring 312 may have the same shape and area.

In a common variation of the embodiments described above with reference to fig. 1-3, the common conductor segment may be part of the adjacent sides of two adjacent rings 110.

In a common variation of the above-described embodiments shown in fig. 1 to 3, the wire segment shared by two adjacent rings 110 may be any position of the wire, provided that the current directions of the two adjacent rings 110 are opposite.

In a common variation of the embodiments shown in fig. 1 to 3, the positions of the current inflow end and the current outflow end can be interchanged, that is, the current can flow into the end portions (e.g., the end portion 111b, the end portion 112b, the end portion 113b, and the end portion 114b) of the respective conductive wires and flow from the start portions (e.g., the start portion 111a, the start portion 112a, the start portion 113a, and the start portion 114 a). At this time, the current directions of the first ring 111 and the third ring 113 included in the first partial ring 120 are both clockwise directions, and the current directions of the second ring 112 and the fourth ring 114 included in the second partial ring 130 are both counterclockwise directions.

In the above-described one common variation of fig. 1 to 3, the number of the even-numbered rings 110 may be 2, and in this case, the shapes and areas of the 2 rings 110 may be equal.

Further, the number of the even number of rings 110 may also be an even number greater than 4, and accordingly, an outer contour of the figure surrounded by the even number of rings 110 may be a polygon.

For example, referring to fig. 4, the inductance structure 400 may include 8 loops 110, wherein each loop 110 may surround a substantially equal area, and an outer contour of a figure surrounded by the inductance structure 400 may be octagonal.

In a common variation of the above-described embodiments of fig. 1 to 3, the thickness of the wires of the different rings 110 may be adjusted such that the magnetic field generated by the first partial ring 120 and the magnetic field generated by the second partial ring 130 substantially cancel each other.

It should be noted that fig. 1 to 3 illustrate an example in which each ring 110 of the even number of rings 110 has a triangular structure, and in practical applications, the rings 110 may also have a rectangular, circular, polygonal, or the like structure.

Although the present invention is disclosed above, the present invention is not limited thereto. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. An inductive structure, comprising:

the even rings are distributed on the same plane around the central point, each ring is formed by winding a conducting wire and is provided with a starting end and a tail end;

each ring and the adjacent ring share the same wire segment, and the current directions of the two adjacent rings are opposite;

the even number of rings includes first partial rings and second partial rings, a current direction of each of the first partial rings is the same, a current direction of each of the second partial rings is the same, and a current direction of each of the first partial rings is opposite to a current direction of each of the second partial rings;

the total area enclosed by each ring in the first partial ring is equal to the total area enclosed by each ring in the second partial ring, and the area of one or more rings in the even number of rings is not equal.

2. The inductor structure of claim 1, wherein an outer contour of the pattern of the even number of rings is an axisymmetric pattern in the plane.

3. The inductor structure of claim 1, wherein the beginning of the conductive line of each loop is coupled to each other and the end of the conductive line of each loop is coupled to each other.

4. The inductive structure of claim 1, wherein the even number of loops is 4.

5. The inductor structure according to claim 4, wherein the 4 loops are a first loop, a second loop, a third loop and a fourth loop in order in a clockwise direction on the plane, the first partial loop comprises the first loop and the third loop, and the second partial loop comprises the second loop and the fourth loop.

6. The inductive structure of claim 5, wherein a sum of areas encompassed by each of the first and third loops is equal to a sum of areas encompassed by each of the second and fourth loops.

7. The inductive structure of claim 5, wherein the first, second, third and fourth loops each enclose an equal area.

8. An inductive structure according to claim 5, characterized in that said first loop and second loop share a first wire segment, said first loop and fourth loop share a second wire segment, said third loop and second loop share a third wire segment, and said third loop and fourth loop share a fourth wire segment.

9. The inductor structure of claim 5, wherein the current inflow end of each of the first, second, third and fourth loops is coupled, and the current outflow end of each of the first, second, third and fourth loops is coupled.