CN221596092U - Planar transformer, circuit board and electronic equipment - Google Patents
Planar transformer, circuit board and electronic equipment Download PDFInfo
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- CN221596092U CN221596092U CN202420633604.9U CN202420633604U CN221596092U CN 221596092 U CN221596092 U CN 221596092U CN 202420633604 U CN202420633604 U CN 202420633604U CN 221596092 U CN221596092 U CN 221596092U
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- 229910001053 Nickel-zinc ferrite Inorganic materials 0.000 description 2
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Abstract
The application relates to the field of transformers, and discloses a planar transformer, a circuit board and electronic equipment. The planar transformer comprises a magnetic core module and a winding module, wherein the magnetic core module comprises a first magnetic core and a second magnetic core which are oppositely arranged, the second magnetic core comprises a body part and a magnetic core center pillar, the body part is covered with the first magnetic core, an air gap is formed between the magnetic core center pillar and the first magnetic core, the winding module is positioned between the body part and the first magnetic core and sleeved on the magnetic core center pillar, the winding module comprises a substrate, a first type winding and a second type winding, the substrate comprises a first wiring layer and a second wiring layer, the first wiring layer is arranged on one side of the substrate close to the air gap, the first type winding is uniformly arranged in a wiring area, the second wiring layer is arranged on the other side of the substrate far away from the air gap, the second type winding is arranged on the second wiring layer, and the number of turns of the first type winding is larger than that of the second type winding. By bringing the winding with a large number of turns close to the air gap and the winding with a small number of turns away from the air gap, the ac loss of the planar transformer can be reduced.
Description
Technical Field
The application relates to the field of transformers, in particular to a planar transformer, a circuit board and electronic equipment.
Background
The planar transformer is a transformer with high frequency, low modeling, very small height and very high working frequency. The greatest difference between planar transformers and traditional transformers is that the planar transformers are made of small-sized E-type, RM-type or ring-shaped ferrite cores, are usually made of high-frequency power ferrite materials, have lower core loss at high frequency, are formed by stacking multiple layers of printed circuit boards, and are formed by stacking windings or copper sheets on planar high-frequency iron cores.
In the traditional planar transformer, when multiple windings are distributed on the multi-layer printed circuit board, a symmetrical design is generally adopted, the winding distribution modes of the symmetrical two-layer printed circuit board are consistent, and the design generally introduces higher alternating current loss, so that the efficiency of the planar transformer is reduced, and the temperature rise is increased.
Disclosure of utility model
An object of the embodiment of the application is to provide a planar transformer, a circuit board and electronic equipment, which can solve the technical problem that the coil windings in the multilayer printed circuit board of the planar transformer are unreasonably distributed to introduce higher alternating current loss in the prior art.
In a first aspect, an embodiment of the present application provides a planar transformer, including:
The magnetic core module comprises a first magnetic core and a second magnetic core, wherein the second magnetic core comprises a body part and a magnetic core middle column, the body part is covered with the first magnetic core, the magnetic core middle column is arranged on one surface of the body part, which faces the first magnetic core, and an air gap is arranged between the magnetic core middle column and the first magnetic core;
The winding module is located between the body part and the first magnetic core and sleeved on the magnetic core center pillar, the winding module comprises a substrate, a first type of winding and a second type of winding, the substrate comprises a first wiring layer and a second wiring layer, the first wiring layer is arranged on one side, close to the air gap, of the substrate, the second wiring layer is arranged on the other side, far away from the air gap, of the substrate, the first type of winding is distributed in a wiring area of the first wiring layer, the second type of winding is uniformly distributed on the second wiring layer, and the number of turns of the first type of winding is larger than that of the second type of winding.
In this embodiment, the winding with a large number of turns is close to the air gap, the winding with a small number of turns is far away from the air gap, so that the influence of the winding with a large number of turns on other windings is avoided, the ac loss of the planar transformer can be reduced, the efficiency of the planar transformer can be improved, and the temperature rise of the planar transformer can be reduced.
In some embodiments, the linewidth of the first type of winding is less than the linewidth of the second type of winding.
In this embodiment, the first type of windings with small line width are arranged on the first layout layer close to the air gap, and the second type of windings with large line width are arranged on the second layout layer far away from the air gap, so that large-area conductors which are easy to generate large current can be avoided to exist near the air gap, eddy current loss of the planar transformer can be reduced, temperature rise of the planar transformer is avoided, and device reliability is improved.
In some embodiments, the first routing layer is disposed a first distance from the first magnetic core and the second routing layer is disposed a second distance from the body portion, the first distance being greater than the second distance.
In this embodiment, since the number of turns of the first type of windings laid on the first wiring layer is larger, the voltage is higher, and the number of turns of the second type of windings laid on the second wiring layer is smaller, the voltage is lower, so that by making the wiring layer with higher voltage farther from the magnetic core body than the wiring layer with lower voltage, the safety problem such as high voltage ignition caused by too short distance between the high voltage coil and the magnetic core body in the use process of the planar transformer can be reduced, and the reliability of the device can be further improved.
In some embodiments, the substrate further comprises an intermediate wiring layer disposed between the first wiring layer and the second wiring layer;
the winding module further comprises a third type of winding, and the third type of winding is arranged on the middle wiring layer.
In this embodiment, by disposing the third-type winding in the intermediate wiring layer between the first wiring layer and the second wiring layer, a reasonable stacking of the planar transformer can be achieved on the basis of satisfying the predetermined design of the transformer.
In some embodiments, the intermediate routing layer is disposed a third distance from the first routing layer, the intermediate routing layer is disposed a fourth distance from the second routing layer, and the third distance and the fourth distance are greater than a preset distance threshold.
In this embodiment, by setting the distance between adjacent wiring layers to be larger than a certain value, it is possible to ensure that the safety requirements are satisfied.
In some embodiments, the third type of winding is a primary winding.
In some embodiments, a part of the wiring area of the second wiring layer is provided with the first type of windings, and the other part of the wiring area of the second wiring layer is provided with the second type of windings; or all coils of the first type of windings are arranged on the first wiring layer, and all coils of the second type of windings are arranged on the second wiring layer; or the first type of windings are distributed in the wiring areas of the first wiring layer.
In some embodiments, the first type of winding is a secondary output winding and the second type of winding is a primary output winding, the secondary output winding having a voltage greater than a voltage of the primary output winding.
In a second aspect, embodiments of the present application provide a circuit board comprising a planar transformer as described above.
In a third aspect, an embodiment of the present application provides an electronic device, including a circuit board as described above.
In the planar transformer provided by the embodiment of the application, the planar transformer comprises a magnetic core module and a winding module, the magnetic core module comprises a first magnetic core and a second magnetic core which are oppositely arranged, the second magnetic core comprises a body part and a magnetic core center pillar, the body part is covered with the first magnetic core, the magnetic core center pillar is arranged on one surface of the body part facing the first magnetic core, an air gap is arranged between the magnetic core center pillar and the first magnetic core, the winding module is positioned between the body part and the first magnetic core and sleeved on the magnetic core center pillar, the winding module comprises a substrate, a first type winding and a second type winding, the substrate comprises a first wiring layer and a second wiring layer, the first wiring layer is arranged on one side of the substrate close to the air gap, the second wiring layer is arranged on the other side of the substrate far away from the air gap, the first type winding is arranged in a wiring area of the first wiring layer, and the second type winding is arranged on the second wiring layer, and the number of turns of the first type winding is larger than that of the second type winding. According to the embodiment, the first winding with relatively more turns is arranged close to the air gap, and the second winding with relatively less turns is arranged far away from the air gap, so that the alternating current loss of the planar transformer can be reduced, the efficiency of the planar transformer can be improved, and the temperature rise of the planar transformer can be reduced.
Drawings
One or more embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements, and in which the figures of the drawings are not to be taken in a limiting sense, unless otherwise indicated.
Fig. 1 is an exploded view of a planar transformer according to an embodiment of the present application;
FIG. 2 is an exploded view of a planar transformer according to an embodiment of the present application;
Fig. 3 is a schematic structural diagram of a winding module according to an embodiment of the present application;
Fig. 4 is a schematic structural view of a winding module according to another embodiment of the present application;
fig. 5 is a schematic structural diagram of a planar transformer according to an embodiment of the present application;
FIG. 6 is a schematic diagram of magnetic core flux according to an embodiment of the present application;
FIG. 7 is a schematic diagram illustrating simulation of AC resistance of a first type of winding according to an embodiment of the present application;
FIG. 8 is a schematic diagram illustrating simulation of the AC resistance of a second type of winding according to an embodiment of the present application;
fig. 9 is a schematic diagram of an application scenario of a planar transformer according to an embodiment of the present application.
Detailed Description
In order that the application may be readily understood, a more particular description thereof will be rendered by reference to specific embodiments that are illustrated in the appended drawings. It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or one or more intervening elements may be present therebetween. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
Unless defined otherwise, 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 application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and/or" as used in this specification includes any and all combinations of one or more of the associated listed items.
The embodiment of the application provides a planar transformer. Referring to fig. 1 to 4, a planar transformer 100 includes a magnetic core module 10 and a winding module 20.
The core module 10 includes a first core 11 and a second core 12 disposed opposite to each other.
The first magnetic core 11 is mainly made of a magnetic core body material, wherein the magnetic core body material may include ferrite, silicon steel sheet, etc., and ferrite may be nickel zinc ferrite, manganese zinc oxide, and nickel zinc oxide, and a person skilled in the art may select a suitable magnetic core body material according to actual requirements.
The core shape of the first magnetic core 11 may be any shape such as E-type, I-type, etc., and those skilled in the art can select an appropriate core shape according to actual needs.
The second magnetic core 12 is mainly made of a magnetic core material, wherein the magnetic core material may include ferrite, silicon steel sheet, etc., and ferrite may be nickel zinc ferrite, manganese zinc oxide, and nickel zinc oxide, and a person skilled in the art may select a suitable magnetic core material according to actual needs. In general, the second core 12 and the first core 11 are made of the same core material.
The second magnetic core 12 includes a body portion 121 and a core middle pillar 122, where the body portion 121 covers the first magnetic core 11, the body portion 121 is in a straight plate shape, the core middle pillar 122 is disposed on one surface of the body portion 121 facing the first magnetic core 11, the core middle pillar 122 and the body portion 121 are integrally formed, the cross-section of the core middle pillar 122 can be any shape such as a circle, a square, etc., and an air gap 10a is disposed between the core middle pillar 122 and the first magnetic core 11. The air gap 10a serves to reduce the permeability, so that the characteristics of the wire wei are less dependent on the initial permeability of the core material, and the air gap 10a can also avoid the phenomenon of magnetic saturation under a large alternating current signal or direct current bias, and the inductance is better controlled.
In some embodiments, the second magnetic core 12 further includes two legs 123, where the legs 123 are disposed on the body portion 121, the number of the legs 123 is two, each leg 123 protrudes from two sides of a surface of the body portion 121 facing the first magnetic core 11, the two legs 123 are respectively abutted against the first magnetic core 11, and a cross-section shape of the legs 123 may be any shape such as square, circular, etc.
The winding module 20 is located between the body portion 121 and the first magnetic core 11, the winding module 20 is provided with a through hole corresponding to the magnetic core middle post 122, the magnetic core middle post 122 passes through the through hole, and the winding module 20 is sleeved on the magnetic core middle post 122 through the through hole.
The winding module 20 includes a substrate 21, a first type of winding 22, and a second type of winding 23.
The substrate 21 is a basic material for arranging the first type winding 22 and the second type winding 23, and in general, the substrate 21 is a copper clad laminate, and in the process of manufacturing the winding module 20, the first type winding 22 and the second type winding 23 are arranged on the substrate 21 by selectively performing processing such as punching, electroless copper plating, electrolytic copper plating, etching and the like on the substrate 21, so as to obtain the winding module 20.
The substrate 21 includes a first wiring layer 211 and a second wiring layer 212, where the first wiring layer 211 is disposed on one side of the substrate 21 near the air gap 10a (the side near the air gap 10a refers to a certain area or a certain number of areas closest to the air gap 10a along the axial direction of the substrate 21), and the second wiring layer 212 is disposed on the other side of the substrate 21 far from the air gap 10a (the other side far from the air gap 10a refers to a certain area or a certain number of areas far from the air gap 10a along the axial direction of the substrate 21 relative to the first wiring layer 211), and the first type windings 22 are disposed on the wiring area of the first wiring layer 211, for example, the first type windings 22 may be disposed on a part of the wiring area of the first wiring layer 211, or the other part of the wiring area may be left free. The first type winding 22 includes a plurality of turns, the number of turns of the first type winding 22 may be set according to actual needs, for example, 10 turns, 15 turns, 20 turns, etc., the first type winding 22 may not be limited to be disposed on the first wiring layer 211, but may also be disposed on other wiring layers, for example, in a case where the number of turns of the first type winding 22 is small, the first wiring layer 211 can accommodate all the turns of the first type winding 22, then all the turns of the first type winding 22 need only be disposed on the first wiring layer 211 and not need to be disposed on other wiring layers, and in a case where the number of turns of the first type winding 22 is large, the first wiring layer 211 cannot accommodate all the turns of the first type winding 22, then a portion of the turns of the first type winding 22 need to be disposed on the first wiring layer 211 and the rest of the turns need to be disposed on other wiring layers.
The second type of windings 23 are uniformly distributed on the second wiring layer 212, so that the second type of windings 23 can be all arranged on the second wiring layer 212, the second type of windings 23 comprise a plurality of turns of coils, the number of turns of the coils of the second type of windings 23 can be set according to practical requirements, for example, 1 turn, 2 turns or 3 turns, and the number of turns of the coils of the second type of windings 23 is smaller than the number of turns of the coils of the first type of windings 22, and in some embodiments, the number of turns of the coils of the first type of windings 22 is 5 to 10 times the number of turns of the coils of the second type of windings 23.
When the first wiring layer 211 cannot accommodate all the coils of the first type winding 22, part of the coils of the first type winding 22 may be disposed on the second wiring layer 212, and at this time, the second wiring layer 212 may be disposed with not only the second type winding 23 but also part of the coils of the first type winding 22.
In some embodiments, a first type of winding 22 is disposed on one portion of the wiring area of the second wiring layer 212, and a second type of winding 23 is disposed on the other portion of the wiring area of the second wiring layer 212, so as to avoid electromagnetic interference, and facilitate miniaturization design of the planar transformer.
In some embodiments, when the first wiring layer 211 is capable of accommodating all coils of the first type of winding 22, all coils of the first type of winding 22 are disposed on the first wiring layer 211 and all coils of the second type of winding 23 are disposed on the second wiring layer 212.
For power schemes of electronic devices such as televisions, commercial displays, etc., flyback power topologies having two power outputs are generally adopted, wherein one power output serves as a main output, the voltage of the main output is relatively low, the other power output serves as an auxiliary output, the voltage of the auxiliary output is relatively high, the energy of the main power output is derived from a main output winding of a transformer, and the energy of the auxiliary power output is derived from an auxiliary output winding of the transformer.
In some embodiments, the first type of winding 22 is a secondary output winding and the second type of winding 23 is a primary output winding, the voltage of the secondary output winding being greater than the voltage of the primary output winding. The first type winding 22 and the second type winding 23 are different secondary windings of the planar transformer 100, the planar transformer 100 can output different voltages through the first type winding 22 and the second type winding 23, wherein the secondary winding with small output voltage can be used as a main output winding, the secondary winding with large output voltage can be used as an auxiliary output winding, and since the number of turns of a coil of the first type winding 22 is larger than that of the coil of the second type winding 23, the output voltage of the first type winding 22 is larger than that of the second type winding 23, the first type winding 22 can be used as an auxiliary output winding, and the second type winding 23 can be used as a main output winding.
For a planar transformer with multiple layers of multi-turn coils, referring to fig. 5, the planar transformer is composed of n layers of coils, each layer of coils is composed of m n turns, and the distance from the n-th layer of coils to the air gap 10a is L n. Assuming that the current and the line width of each coil of the same layer are equal, the current of each coil of the nth layer is I n, the line width of each coil of the nth layer is W n, and the skin effect loss and the proximity effect loss of each coil are deduced according to Maxwell equation set:
wherein P ac1 is the skin effect loss of the N-th layer coil, ρ is the resistivity of copper wire, W n is the width of each turn of coil in the N-th layer coil, N n is the number of turns of copper foil coil of the N-th layer coil, I n is the current of each turn of coil in the N-th layer coil, K s1 is the skin effect coefficient, and P ac2 is the skin effect loss of the N-th layer coil.
Skin effect loss refers to alternating current loss generated by skin effect, and skin effect refers to a phenomenon that current distribution inside a conductor is uneven when alternating current or alternating magnetic field exists in the conductor. The proximity loss refers to an ac loss caused by a proximity effect, which is a phenomenon in which ac currents approach each other to adjacent conductors in two conductors of a two-wire transmission line.
As can be seen from the formula one, the skin effect loss of each layer of coil is mainly influenced by the line width of the coil and the number of turns of the copper foil coil, and the coil width and the number of turns of the copper foil coil of each type of winding are determined when the planar transformer is designed, so that the influence of the layer on the overall skin effect loss, in which each type of winding is arranged, is extremely small.
As can be seen from the formula two, the closer the winding coil is to the air gap, the stronger the influence of the proximity effect, because the winding coil closer to the air gap is also influenced by the winding coil farther to the air gap, thereby generating additional proximity effect loss.
Since the first-type winding 22 is disposed closer to the air gap than the second-type winding 23, the more the first-type winding 22 is affected by the proximity effect of the second-type winding 23, the more the proximity effect loss of the first-type winding 22 is.
In the present embodiment, by arranging the first-type winding 22 with a large number of turns on the first wiring layer 211 closer to the air gap than the second wiring layer 212 and arranging the second-type winding 23 on the second wiring layer 212, the influence of the second-type winding 23 on the proximity effect of the first-type winding 22 can be reduced, and the sum of the proximity effect losses of both the first-type winding 22 and the second-type winding 23 can be reduced. Since the ac loss of the winding module 20 is composed of the skin effect loss and the proximity effect loss, as described above, although the skin effect loss of the winding module 20 varies little, by reasonably distributing and arranging the first type winding 22 and the second type winding 23 in the winding module 20, the proximity effect loss of the winding module 20 can be reduced by arranging the first type winding 22 having a large number of turns closer to the air gap than the second type winding 23 having a small number of turns, and thus the ac loss of the winding module 20 can be reduced as a whole.
Since the first type winding 22 as the auxiliary output winding has a high output voltage and a large number of turns, the coil of the first type winding 22 can be designed to be thin, while the second type winding 23 as the main output winding has a low output voltage and a small number of turns, and the coil of the second type winding 23 can be designed to be thick. In some embodiments, the linewidth of the first type of windings 22 is less than the linewidth of the second type of windings 23.
For a magnetic core with an air gap, referring to fig. 6, the main magnetic flux is concentrated in the magnetic core and follows a main magnetic flux path in the magnetic core, the magnetic core generates a diffusion magnetic flux near the air gap, the diffusion magnetic flux affects a closed conductor near the magnetic core, and according to faraday's law of electromagnetic induction, an alternating magnetic field passes through the closed conductor to generate current on the conductor, that is, the larger the area of the conductor is, the more magnetic flux passes through the conductor, so that the generated current is larger, the current generated by the conductor is called eddy current, the existence of the eddy current causes eddy current loss to be generated by the magnetic core, and the eddy current loss is emitted in the form of heat, so that the temperature rise of the magnetic core is higher, and the reliability of a device is affected.
Therefore, in this embodiment, the second type winding 23 with a large wire width is disposed further away from the air gap than the first type winding 22 with a small wire width, so that a large area of conductor which is easy to generate a large current is prevented from being present near the air gap, thereby reducing eddy current loss of the planar transformer 100, avoiding too high temperature rise of the planar transformer 100, and further improving the reliability of the device.
Since the second-type winding 23 with a large wire width is disposed far from the air gap, compared with the conventional symmetrical design, the present embodiment can reduce the ac resistance of the second-type winding 23, thereby reducing the ac loss of the planar transformer 100.
It can be appreciated that by using the first type of winding 22 with a large number of turns and a small line width as the auxiliary output winding of the transformer and using the first type of winding 22 with a small number of turns and a large line width as the main output winding of the transformer, the present embodiment can be well applied to a flyback power supply topology with two paths of power supply outputs, and by improving the layout of the main output winding and the auxiliary output winding on a multilayer printed circuit board, the present embodiment can avoid excessively high temperature rise of the planar transformer 100 by arranging the auxiliary output winding on the first wiring layer 211 closer to the air gap and arranging the main output winding on the second wiring layer 212 farther from the air gap than the auxiliary output winding, on the one hand, the present embodiment can reduce the proximity loss of the winding module 20, so as to reduce the ac loss of the winding module 20 as a whole, and on the other hand, the present embodiment can reduce the eddy current loss of the planar transformer 100, further reduce the loss of the planar transformer 100, and the reduction of the eddy current loss can avoid excessively high temperature rise, so as to improve the reliability of the device.
Fig. 7 is a schematic diagram illustrating simulation of ac resistance of the first type winding 22 according to an embodiment of the present application. As shown in fig. 7, curve 1 is an ac resistance change curve of the first type winding 22, curve 2 is an ac resistance change curve of the first type winding in a conventional symmetrical design, and as can be seen from fig. 7, the ac resistance of the first type winding 22 is 10% -50% smaller than the ac resistance of the first type winding in a conventional symmetrical design in the full frequency range, and the higher the frequency is, the more obvious the reduction amplitude of the ac resistance is, so that the advantage of the embodiment is more obvious for the loss of high-frequency harmonic waves.
Fig. 8 is a schematic diagram illustrating simulation of ac resistance of the second type winding 23 according to an embodiment of the present application. As shown in fig. 8, the curve 3 is an ac resistance variation curve of the second type winding 23, and the curve 4 is an ac resistance variation curve of the second type winding in the conventional symmetrical design, and as can be seen from fig. 8, the ac resistance of the second type winding 23 is 10% -50% smaller than the ac resistance of the conventional symmetrical design in the full frequency range, and the higher the frequency is, the more obvious the ac resistance is reduced, so that the advantage of the embodiment is more obvious for the loss of high-frequency harmonic waves.
In some embodiments, the first routing layer 211 is disposed a first distance from the first magnetic core 11 and the second routing layer 212 is disposed a second distance from the body portion 121, the first distance being greater than the second distance.
As described above, since the voltage of the first type winding 22 disposed on the first wiring layer 211 is higher than the voltage of the second type winding 23 disposed on the second wiring layer 212, the distance between the first type winding 22 and the core body, which is higher in voltage, needs to be considered in order to reduce the safety risk due to the high voltage. Although the planar transformer 100 has a small height, the present embodiment can reduce the safety problems such as high voltage ignition caused by too close distance between the high voltage coil and the magnetic core body during use of the planar transformer 100 by disposing the first type winding 22 with higher voltage as far as possible from the magnetic core body and disposing the second type winding 23 with lower voltage as close as possible to the magnetic core body, thereby further improving the device reliability.
In some embodiments, referring to fig. 4, the substrate 21 further includes an intermediate wiring layer 213 disposed between the first wiring layer 211 and the second wiring layer 212, and the winding module 20 further includes a third type of winding 24, where the third type of winding 24 is disposed on the intermediate wiring layer 213.
In some embodiments, the third type of winding 24 is a primary winding.
The working principle of the planar transformer 100 provided by the present application is described below with reference to fig. 9.
When the planar transformer 100 works, the MOS transistor Q1 is in a high-frequency switch state in response to an input PWM (pu l se width modu l at ion ) signal, when the MOS transistor Q1 is in an on state, the third winding 24 of the planar transformer 100 stores energy, when the MOS transistor Q1 is in an off state, the energy stored in the third winding 24 of the planar transformer 100 is respectively coupled to the first winding 22 of the planar transformer 100 and the second winding 23 of the planar transformer 100 through the magnetic core module 10, through continuous coupling, the first winding 22 of the planar transformer 100 and the second winding 23 of the planar transformer 100 can generate alternating currents, the alternating current generated by the first winding 22 of the planar transformer 100 is provided as an auxiliary circuit power output to the load Ro2 through the rectification and filtration of the diode D2 and the capacitor C2, and the alternating current generated by the second winding 23 of the planar transformer 100 is provided as a main circuit power output to the load Ro1 through the rectification and filtration of the diode D1 and the capacitor C1.
In some embodiments, the intermediate wiring layer 213 is disposed a third distance from the first wiring layer 211, the intermediate wiring layer 213 is disposed a fourth distance from the second wiring layer 212, and the third and fourth distances are greater than a preset distance threshold.
The preset distance threshold is the minimum distance between the primary winding (i.e. the third type winding 24) and the secondary winding (i.e. the first type winding 22 or the second type winding 23) of the planar transformer 100, which meets the safety requirements, and a person skilled in the art can select a suitable preset distance threshold according to the actual requirements.
In some embodiments, the predetermined distance threshold is 0.45 mm, and it is understood that the third distance and the fourth distance may be any suitable distance greater than 0.45 mm, for example, the third distance and the fourth distance are both 0.5mm.
In some embodiments, referring to fig. 4, the substrate 21 further includes a first insulating dielectric layer 214 and a second insulating dielectric layer 215, the first insulating dielectric layer 214 is disposed between the first wiring layer 211 and the intermediate wiring layer 213, the second insulating dielectric layer 215 is disposed between the intermediate wiring layer 213 and the second wiring layer 212, the first insulating dielectric layer 214 is used for maintaining insulation between the wires of the first wiring layer 211 and the wires of the intermediate wiring layer 213, and the second insulating dielectric layer 215 is used for maintaining insulation between the wires of the second wiring layer 212 and the wires of the intermediate wiring layer 213, so as to ensure safe operation of the circuit. The thickness and material of the first insulating dielectric layer 214 or the second insulating dielectric layer 215 can be selected by those skilled in the art according to actual requirements, and are not limited herein.
In some embodiments, intermediate wiring layer 213 may include one wiring layer or may include a plurality of wiring layers, and one skilled in the art may determine the number of wiring layers of intermediate wiring layer 213 in combination with the number of turns of third type winding 24 or other practical requirements.
In some embodiments, as shown in fig. 4, the intermediate wiring layer 213 includes a third wiring layer 2131 and a fourth wiring layer 2132, the third wiring layer 2131 and the fourth wiring layer 2132 are stacked, the third wiring layer 2131 is close to the first wiring layer 211 with respect to the fourth wiring layer 2132, the fourth wiring layer 2132 is close to the second wiring layer 212 with respect to the third wiring layer 2131, and the third type winding 24 is arranged on the third wiring layer 2131 and the fourth wiring layer 2132.
In some embodiments, as shown in fig. 4, the substrate 21 further includes a third insulating dielectric layer 216 disposed between the third wiring layer 2131 and the fourth wiring layer 2132. The thickness and material of the third insulating dielectric layer 216 can be selected by those skilled in the art according to actual requirements, and are not limited herein.
As another embodiment of the present application, an embodiment of the present application provides a circuit board including the planar transformer 100 as described above. The circuit board can be an independent circuit board or a circuit board formed by splicing a plurality of circuit boards.
As still another embodiment of the application, an embodiment of the present application further provides an electronic device, which includes the circuit board as described above.
Finally, it is to be noted that the present application may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, which are not to be construed as additional limitations on the scope of the application, but rather as providing for a more thorough understanding of the present application. And under the idea of the application, the technical features described above are continuously combined with each other, and many other variations exist in different aspects of the application as described above, which are all considered as the scope of the description of the application; further, modifications and variations of the present application may be apparent to those skilled in the art in light of the foregoing teachings, and all such modifications and variations are intended to be included within the scope of this application as defined in the appended claims.
Claims (10)
1. A planar transformer, comprising:
The magnetic core module comprises a first magnetic core and a second magnetic core which are oppositely arranged, the second magnetic core comprises a body part and a magnetic core middle column, the body part is covered with the first magnetic core, the magnetic core middle column is arranged on one surface of the body part, which faces the first magnetic core, and an air gap is arranged between the magnetic core middle column and the first magnetic core;
The winding module is located between the body part and the first magnetic core and sleeved on the magnetic core center pillar, the winding module comprises a substrate, a first type of winding and a second type of winding, the substrate comprises a first wiring layer and a second wiring layer, the first wiring layer is arranged on one side, close to the air gap, of the substrate, the second wiring layer is arranged on the other side, far away from the air gap, of the substrate, the first type of winding is distributed in a wiring area of the first wiring layer, the second type of winding is uniformly distributed on the second wiring layer, and the number of turns of the first type of winding is larger than that of the second type of winding.
2. The planar transformer of claim 1, wherein the linewidth of the first type of windings is less than the linewidth of the second type of windings.
3. The planar transformer of claim 1, wherein the first routing layer is disposed a first distance from the first magnetic core and the second routing layer is disposed a second distance from the body portion, the first distance being greater than the second distance.
4. A planar transformer as claimed in claim 1, wherein,
The substrate further includes an intermediate wiring layer disposed between the first wiring layer and the second wiring layer;
the winding module further comprises a third type of winding, and the third type of winding is arranged on the middle wiring layer.
5. The planar transformer of claim 4, wherein the intermediate wiring layer is disposed a third distance from the first wiring layer, the intermediate wiring layer is disposed a fourth distance from the second wiring layer, and the third distance and the fourth distance are greater than a preset distance threshold.
6. The planar transformer of claim 4, wherein the third type of winding is a primary winding.
7. The planar transformer according to claim 1, wherein the second wiring layer has a wiring region in which the first type of windings are provided and a wiring region in which the second type of windings are provided; or all coils of the first type of windings are arranged on the first wiring layer, and all coils of the second type of windings are arranged on the second wiring layer; or the first type of windings are distributed in the wiring areas of the first wiring layer.
8. The planar transformer of any one of claims 1 to 7, wherein the first type of winding is an auxiliary output winding, the second type of winding is a main output winding, and the auxiliary output winding has a voltage greater than a voltage of the main output winding.
9. A circuit board comprising a planar transformer as claimed in any one of claims 1 to 8.
10. An electronic device comprising the circuit board of claim 9.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202420633604.9U CN221596092U (en) | 2024-03-28 | 2024-03-28 | Planar transformer, circuit board and electronic equipment |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202420633604.9U CN221596092U (en) | 2024-03-28 | 2024-03-28 | Planar transformer, circuit board and electronic equipment |
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| CN221596092U true CN221596092U (en) | 2024-08-23 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN119252615A (en) * | 2024-11-21 | 2025-01-03 | 广州视珩电子科技有限公司 | A planar transformer and power supply device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN119252615A (en) * | 2024-11-21 | 2025-01-03 | 广州视珩电子科技有限公司 | A planar transformer and power supply device |
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