Integrated power supply using planar energy transfer element
The integration of control devices and power circuit components on a stack of circuit layers with a planar transformer core addresses the challenge of EMI in conventional power converters, resulting in a compact and efficient DC-DC power converter design.
Patent Information
- Application Number
- JP2024197039
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-12-15
- Filing Date
- 2024-11-11
- Publication Date
- 2025-07-08
AI Technical Summary
Conventional power converters face challenges in integrating control devices and circuit components efficiently due to the need for separate mounting to minimize electromagnetic interference (EMI) and parasitic noise, which complicates the design and increases size and complexity.
A DC-DC power converter design that integrates control devices and power circuit components on a stack of circuit layers with a planar energy transfer element, such as a planar transformer, where the magnetic core is located within a hole, allowing for compact integration of input and output windings and connections, and the control device communicates between the input and output sides.
This design reduces EMI noise, minimizes physical separation of components, and enhances efficiency by integrating control devices and power circuit components in a compact form, thus improving the overall performance and reducing the converter's size and complexity.
Smart Images
Figure 2025102660000001_ABST
Abstract
Description
Technical Field
[0001]
[0001] This disclosure generally relates to power converters, and more particularly, to the packaging of power converters.
Background Art
[0002]
[0002] Electric utilities transmit unregulated alternating current (AC) over long distances and between buildings. This transmission requires very high voltages that most circuits within homes and offices, such as electronic devices, cannot handle. The voltage needs to be reduced to be used in those environments. Similarly, high-voltage batteries are used to power the motors of electric vehicles. The battery voltage output needs to be reduced to power internal accessories such as windows, radios, and navigation systems. A switching power converter, also known as a switching-mode power converter, is commonly used by many current electronic devices to provide a lower voltage due to its high efficiency, small size, and light weight. The switching-mode power converter converts the high voltage associated with the unregulated AC input into a lower voltage associated with a constant or stable direct current (DC) output, also known as a regulated DC output, through an energy transfer element such as a transformer. The switching-mode power converter typically provides DC output regulation by detecting one or more signals representing one or more output quantities, such as voltage, current, or a combination of the two, and controlling the output in a closed loop. During operation, the switch is toggled on and off to provide the desired output by changing the duty cycle, changing the switching frequency, or changing the number of pulses per unit time of the switch in the switching-mode power converter.
[0003]
[0003] A power converter generally includes one or more control devices that detect the output of the power converter and control the operation of switches to regulate the output. These control devices generally require a regulated or unregulated voltage source to power the circuit components of the control device.
SUMMARY OF THE INVENTION
[0004]
[0004] With reference to the following figures, non-limiting and non-exhaustive embodiments of the present invention are described, and like reference numerals indicate like parts throughout the various drawings, unless otherwise specified. Corresponding reference numerals indicate corresponding components throughout multiple views of the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005]
Figure 1
[0005] FIG. 1 shows a circuit schematic of circuit components for a direct current (DC)-DC power converter 30 according to the present disclosure.
Figure 2
[0006] FIG. 2 shows an exemplary top-down view of the layout of the DC-DC power converter 30 shown in FIG. 1, where the control device 32 and the power circuit components are located, illustratively, within an area 38c of a planar energy transfer element 38 and outside of a magnetic core assembly 48.
Figure 3A
[0007] FIGS. 3A - 3B show a power converter assembly including a two-piece E-E or E-I shaped magnetic core. FIG. 3A shows a perspective view. FIG. 3B shows a side view.
Figure 3B
[0007] FIGS. 3A - 3B show a power converter assembly including a two-piece E-E or E-I shaped magnetic core. FIG. 3A shows a perspective view. FIG. 3B shows a side view.
Figure 4
[0008] FIG. 4 is an exploded view of the power converter assembly shown in FIGS. 3A and 3B.
Figure 5
[0009] FIG. 5 is an exploded view showing the electrical connection layer and the winding layer of a simplified stack of the circuit layer 46. DETAILED DESCRIPTION OF THE INVENTION
[0006]
[0010] Across multiple figures in the drawings, corresponding reference numerals indicate corresponding components. Those skilled in the art will understand that the elements in the figures are drawn to be simple and clear, and are not necessarily drawn to scale. For example, the dimensions of some elements in the figures may be exaggerated compared to other elements to make various embodiments of the present invention easier to understand. Furthermore, generally well-understood elements that are useful or necessary in commercially applicable embodiments are often not drawn so as not to obscure the figures of these various embodiments of the present invention.
[0007]
[0011] Conventional power converters include energy transfer elements such as discrete transformers including an input winding and an output winding. Discrete transformers are typically mounted on a printed circuit board. Transformers, and any other power converter circuit components, are physically separated from each other to minimize EMI and parasitic noise from resistors, inductance, and capacitance.
[0008]
[0012] The disclosed embodiments relate to a DC-DC power converter including a power circuit component mounted on a stack of circuit layers including a planar energy transfer element such as a planar transformer. A hole extends through each of the circuit layers. A magnetic core assembly is located within the hole. A portion of the stack of circuit layers includes an input winding layer and an output winding layer. Each winding layer includes a winding and a connection for electrical connectivity. The power converter circuit component includes input and output circuit components mounted within the area of the stack and external to the magnetic core. The area of the stack accommodates the larger of the input and output winding layers, the windings and the connections for electrical connectivity. In an embodiment, the input circuit component may be mounted on the stack of circuit layers and electrically connected to the input winding layer. In an embodiment, the output circuit component may be mounted on the stack of circuit layers and electrically connected to the output winding layer.
[0009]
[0013] FIG. 1 shows a circuit schematic of circuit components for a DC-DC power converter 30 according to the present disclosure. A control device 32 is connected to a power switch 35, a synchronous rectifier 34, and further power converter components including a planar energy transfer element 38, such as a planar transformer, a filter circuit 40, a detection circuit 42, and a feedback circuit 44. The planar energy transfer element 38 is integrated in a stack 46 of circuit layers. When the planar energy transfer element 38 is a transformer, the input winding 38a is a primary winding and the output winding 38b is a secondary winding. Each of the windings includes at least one winding layer. The control device 32 and the further power converter circuit components are located on the stack 46 such that they are within an area 38c (shown in FIG. 2) of the stack 46 of circuit layers. The area 38c of the stack 46 of circuit layers accommodates the larger of the input winding 38a and the output winding 38b, the windings and the connections for electrical connectivity. Embodiments of the converter 30 may optionally form part of an AC-DC converter with an added bridge rectifier and input capacitance (shown by the gray scale within box 16) as would be understood by one of ordinary skill in the art.
[0010]
[0014] Figure 2 is an exemplary top-down view of the layout of a DC-DC power converter 30 shown in FIG. 1, showing that the control device 32 and further power circuit components, such as the power switch 35, synchronous rectifier 34, filter circuit 40, detection circuit 42, and feedback circuit 44, are illustratively located within the area 38c of the planar energy transfer element 38 and outside the magnetic core assembly 48. The magnetic core assembly 48 extends through the stack 46 of circuit layers. The power converter circuit components can be located on one or both of the first surface 46a or the second surface 46b of the stack 46 of circuit layers. The first and second surfaces are parallel to the circuit layers. An optional housing (not shown) can enclose the stack 46 of circuit layers, the magnetic core assembly 48, and the power converter circuit components.
[0011]
[0015] The stack 46 of circuit layers includes holes extending through each of the circuit layers. A portion of the magnetic core assembly 48 and the stack 46 of circuit layers form a planar energy transfer element 38, such as a planar transformer. A portion of the stack 46 of circuit layers includes an input winding 38a and an output winding 38b. Each winding includes at least one winding layer. The winding layer includes a planar winding and a connection for electrical connectivity. The planar winding can be a circular spiral or an oval spiral with one or more turns. The magnetic core assembly 48 is located within a hole that is substantially orthogonal to the stack 46 of circuit layers. The area 38c of the planar energy transfer element 38 is in the same plane as the first surface and houses the connection for the electrical connectivity between the winding and the input winding layer 38a and the output winding layer 38b.
[0012]
[0016] The control device 32, the input winding 38a, and the output winding 38b are electrically connected to the power converter circuit components. The control device 32 facilitates communication between the input side and the output side of the power converter.
[0013]
[0017] The power converter circuit components are either input circuit components or output circuit components. In this embodiment, the power converter circuit components are mounted on the first surface 46a. A portion of the first surface 46a is omitted to show a layer including one layer of the input winding 38a. The input circuit components are mounted within the area 38c of the input winding 38a and the output winding 38b and outside the magnetic core assembly 48, and are electrically connected to the input winding 38a. The output circuit components are mounted within the area 38c of the input winding 38a and the output winding 38b and outside the magnetic core assembly 48, and are electrically connected to the output winding 38b. The input circuit components include a power switch 35. The output circuit components include a synchronous rectifier 34, a filter circuit 40, a detection circuit 42, and a feedback circuit 44.
[0014]
[0018] FIGS. 3A-3B show a power converter assembly including a two-piece E-E or E-I magnetic core. FIG. 3A shows a perspective view. FIG. 3B shows a side view.
[0015]
[0019] FIG. 3A shows that the power converter circuit components are mounted on the first surface 46a and overlap and are mounted on one or more portions of the windings of the input winding 38a and the output winding 38b. The power converter circuit components may further overlap and be mounted on one or more portions of the connection portions for the electrical connectivity of the input winding 38a and the output winding 38b.
[0016]
[0020] FIG. 3B shows that the power converter circuit components may be further mounted on the second surface 46b of the stack of circuit layers 46. The first surface 46a and the second surface 46b are substantially parallel to each other.
[0017]
[0021] In one variation, all of the power converter circuit components are mounted on the same surface of the stack and outside the magnetic core. The surface may be the first surface 46a or the second surface 46b.
[0018]
[0022] In one variation, the input circuit component is mounted on one of the first surface 46a and the second surface 46b, and the output circuit component is mounted on the other of the first surface 46a and the second surface 46b.
[0019]
[0023] In one variation, the first portion of the power converter circuit component is mounted on the first surface 46a, and the second portion of the power converter circuit component is mounted on the second surface 46b.
[0020]
[0024] The two-piece magnetic core assembly 48 can be an E-I core or an E-E core. In an E-I core, the "I" is disposed near the open end of the "E" so as to form a three-legged structure. In an E-E core, the corresponding legs of the "E" are disposed close to each other. The "E" has an equal height. Those skilled in the art will understand that any magnetic core assembly can be located within the holes of the stack 46 of circuit layers.
[0021]
[0025] In a two-piece E-I or E-E core, the magnetic core assembly 48 has a window. The planar energy transfer element 38 is surrounded by the magnetic core assembly 48 and is located within the window. The central leg of the "E" extends through the hole of the stack 46 of circuit layers.
[0022]
[0026] FIG. 4 is an exploded view of the magnetic core 48 and the stack 46 of circuit layers shown in FIGS. 3A and 3B. The magnetic core assembly 48 is a two-piece E-I shaped magnetic core including a central leg. The central leg 48a is substantially orthogonal to the stack 46 of circuit layers and extends through the hole of the stack 46 of circuit layers. When the two parts of the core are brought together, there is a gap between the end of the central leg 48a of the core and the I part 48b.
[0023]
[0027] FIG. 5 is an exploded view showing the electrical connectivity layer and the winding layer of the stack 46 of simplified circuit layers. In this embodiment, each circuit layer is a layer of a multilayer printed circuit board. Those skilled in the art will understand that each circuit layer can be formed as an individual printed circuit board, which is later assembled into a stack.
[0024]
[0028] In this simplified embodiment, the first surface 46a and the second surface 46b are connectivity layers. The connectivity layer can include copper wiring used in a power converter to provide electrical connectivity within the stack 46.
[0025]
[0029] For the input winding layer 38a and the output winding layer 38b, the windings can be circular or oval spirals, and thus may not necessarily reach the corners of the PCB layer. These corners can include connections for electrical connectivity, such as pads, vias, and wiring, to achieve electrical connectivity to the circuit layer. For each type of winding layer, such as input and output, there can be multiple winding layers.
[0026]
[0030] The area 38c of the planar energy transfer element is restricted by circuit features that occupy most of the surface. The area 38c of the planar energy transfer element can include the larger of the input winding 38a and the output winding 38b and the connections for electrical connectivity. Since the number of turns (the turns are the revolutions around the central hole), the pitch between the turns, or even the cross-sectional area of the conductor making the turns can be different, the input winding 38a and the output winding 38b do not necessarily occupy the same area. The power circuit components are located near and overlap any of the windings and the connections for the associated electrical connectivity.
[0027]
[0031] Each circuit layer can be a printed circuit board or a sublayer in a printed circuit board. The sublayer can include isolation and insulation layers to reduce electromagnetic interference (EMI) noise, to provide stress relief, or to provide electrical insulation between circuit components in a DC-DC converter.
[0028]
[0032] Many specific details have been set forth herein in order to provide a thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced without these specific details. For example, well-known materials or methods have not been described in detail in order to avoid obscuring the present invention. For example, those skilled in the art will understand that the elements in the foregoing figures are drawn simply and clearly and are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements in order to make the various embodiments of the present invention easier to understand. Further, commonly understood elements that are useful or necessary in a commercially suitable embodiment are often not shown in the figures so as not to obscure the figures of these various embodiments of the present invention.
[0029]
[0033] References in this specification to "one embodiment", "an embodiment", "an example", or "an example" mean that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment of the present invention. Thus, the appearances of the phrases "in one embodiment", "in an embodiment", "an example", or "an example" in various places in this specification are not necessarily all referring to the same embodiment or example. Further, the particular features, structures, or characteristics may be combined in any suitable combination and / or sub-combination in one or more embodiments or examples. The particular features, structures, or characteristics may be included in an integrated circuit, an electronic circuit, a combinational logic circuit, or other suitable component that provides the described functionality.
[0030]
[0034] The description of the illustrated examples of the present invention is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Specific embodiments and examples of the invention are described herein for illustrative purposes, but various equivalent modifications can be made without departing from the broader spirit and scope of the invention. In fact, it is understood that any specific and exemplary voltage, current, frequency, output range value, time, etc. are presented for purposes of illustration, and that other values may be used in other embodiments and examples according to the teachings of the invention.
[0031]
[0035] The present invention is defined in the claims, but the invention may alternatively be defined by the following examples.
[0032]
[0036] Example 1. A power converter, comprising: a stack of circuit layers including holes extending through each of a first surface and the circuit layers, a portion of the circuit layers forming an energy transfer element, the energy transfer element including an input winding having at least one winding layer and an output winding having at least one winding layer, each winding layer including a winding and a connection for electrical connectivity; a magnetic core located within a hole substantially orthogonal to the stack; an area of the stack of circuit layers on the same plane as the first surface, the area of the stack of circuit layers accommodating the windings and the connections for electrical connectivity of the input and output windings; a power converter circuit component mounted on the first surface of the stack; the power converter circuit component including an input circuit component mounted within the area of the stack and external to the magnetic core, the input circuit component being electrically connected to the input winding, and an output circuit component mounted within the area of the stack and external to the magnetic core, the output circuit component being electrically connected to the output winding.
[0033]
[0037] Example 2. The power converter according to Example 1, wherein the power converter circuit components are further mounted on the second surface of the stack of circuit layers, and the first surface and the second surface are substantially parallel to each other.
[0034]
[0038] Example 3. The power converter according to Example 2, wherein the first part of the power converter circuit components is an input converter component mounted on the first surface, and the second part of the power converter circuit components is an output converter component mounted on the second surface.
[0035]
[0039] Example 4. The power converter according to Example 1, wherein a part of the power converter circuit components is mounted on a part of the windings of the input winding and the output winding.
[0036]
[0040] Example 5. The power converter according to Example 4, wherein a part of the power converter circuit components is further mounted on a part of the connection portion for the electrical connectivity of the input winding and the output winding.
[0037]
[0041] Example 6. The power converter according to Example 1, wherein a part of the power converter circuit components is mounted on a part of the connection portion for the electrical connectivity of the input winding and the output winding.
[0038]
[0042] Example 7. The power converter according to Examples 1 to 6, further comprising a housing surrounding the stack, the magnetic core, and the power converter circuit components.
[0039]
[0043] Example 8. The power converter according to Examples 1 to 7, wherein the magnetic core is an E-E core.
[0040]
[0044] Example 9. The power converter according to Examples 1 to 7, wherein the magnetic core is an E-I core.
[0041]
[0045] Example 10. The power converter described in Examples 1 to 9, wherein the power converter circuit component includes a power switch, a synchronous rectifier, a control device, a filter circuit, a detection circuit, and a feedback circuit.
[0042]
[0046] Example 11. The power converter described in Examples 1 to 10, wherein the stack of circuit layers further includes each circuit layer that is a printed circuit board.
[0043]
[0047] Example 12. The stack of circuit layers is a multilayer printed circuit board. The power converter described in Examples 1 to 10.
[0044]
[0048] Example 13. A magnetic core with a window, and a stack of circuit layers located within the window, wherein a part of the circuit layer forms an energy transfer element, the energy transfer element includes an input winding having at least one winding layer and an output winding having at least one winding layer, each winding layer includes a planar winding and a connection portion for electrical connectivity, a stack area for accommodating the planar winding and the connection portion for electrical connectivity of the input winding and the output winding, and a power converter circuit component mounted on the first surface of the stack and electrically connected to one of the input winding and the output winding, the power converter circuit component being mounted within the stack area and outside the magnetic core.
[0045]
[0049] Example 14. The power converter described in Example 13, wherein the power converter circuit component is further mounted on the second surface of the stack, and the first surface and the second surface are substantially parallel to each other.
[0046]
[0050] Example 15. The power converter described in Example 14, wherein a part of the power converter circuit component is mounted on a part of the windings of the input winding and the output winding.
[0047]
[0051] Example 16. The power converter according to Example 15, wherein a part of the power converter circuit component is mounted on a part of the connection portion for the electrical connectivity of the input winding and the output winding.
[0048]
[0052] Example 17. The power converter according to any one of Examples 13 to 16, further comprising a housing surrounding the stack, the magnetic core, and the power converter circuit component.
[0049]
[0053] Example 18. The power converter according to any one of Examples 13 to 17, wherein the power converter circuit component is selected from the group consisting of a power switch, a synchronous rectifier, a control device, a filter circuit, a detection circuit, and a feedback circuit.
Claims
1. A power converter, wherein the power converter comprises a stack of circuit layers including holes extending through each of a first surface and the circuit layers, a portion of the circuit layers forming an energy transfer element, the energy transfer element comprising an input winding having at least one winding layer and an output winding having at least one winding layer, each said winding layer including a winding and a connection portion for electrical connectivity, said stack of circuit layers; a magnetic core positioned within the hole substantially orthogonal to the stack; an area of the stack of circuit layers that is in the same plane as the first surface and that houses the winding and connection portions for electrical connectivity of the winding with the input winding and the output winding; a power converter circuit component mounted on the first surface of the stack; and wherein the power converter circuit component comprises an input circuit component mounted within the area of the stack and external to the magnetic core, the input circuit component being electrically connected to the input winding; an output circuit component mounted within the area of the stack and external to the magnetic core, the output circuit component being electrically connected to the output winding; and a power converter.
2. The power converter circuit component is further mounted on a second surface of the stack of circuit layers, and the first surface and the second surface are substantially parallel to each other. The power converter according to claim 1.
3. A first portion of the power converter circuit component is an input converter component mounted on the first surface, and a second portion of the power converter circuit component is an output converter component mounted on the second surface. The power converter according to claim 2.
4. A portion of the power converter circuit component is mounted on a portion of the winding of the input winding and the output winding. The power converter according to claim 1.
5. The portion of the power converter circuit component is further mounted on a portion of the connection portion for electrical connectivity of the input winding and the output winding. The power converter according to claim 4.
6. A part of the power converter circuit component is mounted on a part of the connection part for the electrical connectivity of the input winding and the output winding, The power converter according to claim 1.
7. The power converter according to claim 1, further comprising a housing surrounding the stack, the magnetic core, and the power converter circuit component. The power converter according to claim 1.
8. The power converter according to claim 1, wherein the magnetic core is an E-E core. The power converter according to claim 1.
9. The power converter according to claim 1, wherein the magnetic core is an E-I core. The power converter according to claim 1.
10. The power converter according to claim 1, wherein the power converter circuit component includes a power switch, a synchronous rectifier, a control device, a filter circuit, a detection circuit, and a feedback circuit. The power converter according to claim 1.
11. The power converter according to claim 1, wherein the stack of the circuit layer further includes each circuit layer which is a printed circuit board. The power converter according to claim 1.
12. The power converter according to claim 1, wherein the stack of the circuit layer is a multilayer printed circuit board. The power converter according to claim 1.
13. A power converter, wherein the power converter includes A magnetic core having a window, A stack of circuit layers located within the window, a part of the circuit layer forming an energy transfer element, the energy transfer element including an input winding having at least one winding layer and an output winding having at least one winding layer, and each said winding layer including a planar type winding and a connection part for electrical connectivity, the stack of the circuit layer, An area of the stack for accommodating the planar type winding and the connection part for the electrical connectivity of the input winding and the output winding, A power converter circuit component mounted on a first surface of the stack and electrically connected to one of the input winding and the output winding, the power converter circuit component being mounted within the area of the stack and outside the magnetic core, the power converter circuit component, A power converter comprising.
14. The power converter circuit component is further mounted on a second surface of the stack, The first surface and the second surface are substantially parallel to each other, The power converter according to claim 13.
15. Part of the power converter circuit components is mounted on a part of the windings of the input winding and the output winding. The power converter according to claim 14. **Claim 16** The part of the power converter circuit components is mounted on a part of the connection portion for the electrical connectivity of the input winding and the output winding. The power converter according to claim 15. **Claim 17** Further comprising a housing surrounding the stack, the magnetic core, and the power converter circuit components. The power converter according to claim 13. **Claim 18** The power converter circuit components are selected from the group consisting of a power switch, a synchronous rectifier, a control device, a filter circuit, a detection circuit, and a feedback circuit. The power converter according to claim 13.