CN111917310A

CN111917310A - Adapter power supply

Info

Publication number: CN111917310A
Application number: CN201911310616.8A
Authority: CN
Inventors: 魏隆吉; 林哲民; 詹国杰
Original assignee: FSP Technology Inc
Current assignee: FSP Technology Inc
Priority date: 2019-05-10
Filing date: 2019-12-18
Publication date: 2020-11-10
Also published as: TW202042483A; TWI686044B

Abstract

An adapter power supply comprises a circuit board, a power factor correction transistor, a bridge rectifier, a power factor correction inductor, a capacitor and a transformer. The circuit board is provided with a first long edge and a second long edge which are parallel to each other. The power factor correction transistor is arranged on the circuit board and is close to the first long side. The bridge rectifier is arranged on the circuit board and close to the second long side. The power factor correction inductor is disposed on the circuit board and has a first long axis. The first long axis is parallel to the first long side. The capacitor and the power factor correction inductor are arranged on the circuit board side by side along the width direction of the circuit board. The capacitor has a second long axis. The first long axis of the power factor correction inductor is parallel to the second long axis of the capacitor. The transformer is arranged on the circuit board and is positioned beside the power factor correction inductor and the capacitor.

Description

Adapter power supply

Technical Field

The present invention relates to power supplies, and more particularly, to an adapter power supply.

Background

In a conventional adapter power supply, components such as a power factor correction transistor, a bridge rectifier, a power factor correction inductor, a capacitor, and a transformer are usually disposed on a circuit board inside the adapter power supply. Moreover, the power that can be achieved by the adapter power supply is primarily dependent on the electrical parameters and dimensional specifications of the aforementioned components.

Generally, the adapter power source is usually used in portable electronic devices such as notebook computers and game consoles. Thus, the size of the adapter power supply itself is a consideration for the consumer. Accordingly, if the overall size of the adapter power supply can be reduced under the same electrical parameters and dimensions, the portability of the electronic product can be further improved, and the consumer's needs can be satisfied.

Content of application

The invention aims to provide an adapter power supply which can increase the area utilization rate of a circuit board so as to achieve the advantage of high power density.

The invention discloses an adapter Power supply, which comprises a circuit board, a Power Factor Correction (PFC) transistor, a bridge rectifier, a PFC inductance, a capacitor and a transformer. The circuit board is provided with a first long edge and a second long edge which are parallel to each other. The power factor correction transistor is arranged on the circuit board and is close to the first long side. The bridge rectifier is arranged on the circuit board and close to the second long side. The power factor correction inductor is disposed on the circuit board and has a first long axis. The first long axis is parallel to the first long side. The capacitor and the power factor correction inductor are arranged on the circuit board side by side along the width direction of the circuit board. The capacitor has a second long axis. The first long axis of the power factor correction inductor is parallel to the second long axis of the capacitor. The transformer is arranged on the circuit board and is positioned beside the power factor correction inductor and the capacitor.

Preferably, the distance between the first long axis of the power factor correction inductor and the second long axis of the capacitor is between 20 mm and 23 mm.

Preferably, the ratio of the length occupied by the projection of the power factor correction inductor and the capacitor to the circuit board to the length of the circuit board is between 0.2 and 0.4.

Preferably, the circuit board is divided into a first area, a second area and a third area equally divided in the length direction of the circuit board, and the power factor correction inductor and the capacitor are located in the second area of the circuit board.

Preferably, the power factor correction inductor includes a magnetic core, the magnetic core includes a center pillar and two arm portions located at two sides of the center pillar, and each arm portion has an arc-shaped outer contour.

Preferably, the distance between the center of the center pillar and the outer edge of each arm portion is between 15 mm and 17 mm.

Preferably, the angle formed by the connection line between the two ends of each arm portion and the axis of the center pillar is between 85 ° and 90 °.

Preferably, a cross section of the center pillar has a shape in which a portion of a circle is cut off, and the cross section of the center pillar has an area equal to the sum of the cross sections of the arm portions.

Preferably, the ratio of the width to the length of the circumscribed rectangle of the core is between 0.6 and 0.65.

Preferably, the transformer is spaced from the power factor correction inductor by a first distance, the transformer is spaced from the capacitor by a second distance, and a difference between the first distance and the second distance is not more than 5 mm.

Compared with the prior art, the power factor correction inductor and the capacitor of the adapter power supply are arranged side by side along the width direction of the circuit board respectively. Therefore, the long edge of the circuit board can be shortened, the area utilization rate of the circuit board is increased, and the whole volume of the adapter power supply is saved. In addition, the bridge rectifier and the power factor correction inductor are respectively arranged beside the first long side and the second long side which are opposite. Therefore, high heat energy generated by the bridge rectifier and the power factor correction inductor can be dissipated from two opposite sides in a dispersing manner, no extra heat dissipation component is needed to assist heat dissipation, and the overall size of the adapter power supply is further reduced.

Drawings

FIG. 1 is a schematic diagram of an adapter power supply according to an embodiment of the invention.

Fig. 2 is a schematic diagram of the power factor correction inductor of the adapter power supply of fig. 1 shown disassembled.

Fig. 3 is a top view of the core of the power factor correction inductor of fig. 2.

Description of the symbols

100: adapter power supply

110: circuit board

112: first long side

114: second long side

117: first region

118: second region

119: third zone

120: power factor correction transistor

130: bridge rectifier

140: power factor correction inductor

142: first long axis

144: magnetic core

1441: center post

1441 a: transverse section

1443: arm part

146: support frame

150: capacitor with a capacitor element

152: second long axis

160: transformer device

170: input plug

180: output end

190: metal radiating fin

140a, 150a, 160 a: center of symmetry

L110, L144, L150: length of

W110, W144: width of

D1 length direction

D2 width direction

d1: first distance

d2: second distance

d3, d 4: distance between two adjacent plates

θ: included angle

A1: area of

A2: sum of cross-sectional area

Detailed Description

To explain the technical content and the structural features of the present invention in detail, the following description is further made with reference to the embodiments and the accompanying drawings.

With the development of technology, the size of portable electronic products is gradually reduced, and these portable electronic products usually need to be charged by using an adapter power supply. Therefore, as the size of the portable electronic product is smaller and smaller, the size and portability of the adapter power source are also receiving more and more attention. However, the power available from the adapter power supply is related to the size of its internal components. If the high power requirement is to be satisfied at the same time, the size of the internal components may not be reduced, which may affect the overall machine of the adapter power supply. The following description will describe how to make the adapter power supply have better portability by changing the relative position and shape of the components so that the adapter power supply has a smaller volume and a higher power density.

FIG. 1 is a schematic diagram of an adapter power supply according to an embodiment of the present invention. Referring to fig. 1, in the present embodiment, the adapter Power supply 100 includes a circuit board 110, a Power Factor Correction (PFC) transistor 120, a bridge rectifier 130, a PFC inductor 140, a capacitor 150, and a transformer 160. It should be noted that, in the present embodiment, the power factor correction transistor 120, the bridge rectifier 130, the power factor correction inductor 140, the capacitor 150 and the transformer 160 are all disposed on the circuit board 110. In addition, as shown in fig. 1, the circuit board 110 has a first long side 112 and a second long side 114 parallel to each other. The position and relative relationship of the above components on the circuit board 110 will be described in detail below.

Generally, the pfc transistor and the bridge rectifier belong to components that generate high thermal energy. Therefore, in the conventional adapter power supply, the power factor correction transistor and the bridge rectifier are usually configured together. Because the power factor correction transistor and the bridge rectifier generate high heat during operation, heat dissipation needs to be assisted by heat dissipation structures such as heat dissipation fins. However, the heat dissipation structure will occupy a certain volume, which will not reduce the volume of the conventional adapter power supply.

In view of this, in the present embodiment, the power factor correction transistor 120 is located close to the first long side 112 of the circuit board 110. The bridge rectifier 130 is located close to the second long side 114. Of course, in other embodiments, the positions of the pfc transistor 120 and the bridge rectifier 130 in the length direction D1 of the circuit board 110 may be configured appropriately according to actual requirements, as long as the pfc transistor 120 and the bridge rectifier 130 are respectively configured on two opposite sides (the first long side 112 and the second long side 114) of the circuit board 110, and the positions of the pfc transistor 120 and the bridge rectifier 130 in the length direction D1 of the circuit board 110 are not limited in the present invention.

Moreover, in the present embodiment, the first long side 112 and the second long side 114 of the circuit board 110 are further respectively provided with two metal heat sinks 190 perpendicular to the circuit board 110 (for example, emitting from the direction of fig. 1), and the metal heat sinks 190 are respectively in contact with the power factor correction transistor 120 and the bridge rectifier 130, and the power factor correction transistor 120 and the bridge rectifier 130 are thermally coupled to the corresponding metal heat sinks 190. In this way, the heat energy of the power factor correction transistor 120 and the bridge rectifier 130 can be dissipated through the corresponding metal heat sink 190, so as to increase the heat dissipation efficiency of the two.

In other embodiments, the heat sink does not have to be perpendicular to the circuit board 110, and may be configured to reduce the overall occupied volume of the adapter power supply 100. The invention does not limit the material and the arrangement mode of the radiating fin.

In short, in the present embodiment, the power factor correction transistor 120 is configured separately from the bridge rectifier 130. That is, two components of the adapter power supply 100 of the present embodiment that generate high thermal energy are separately disposed on two opposite sides. Based on the design, no additional heat dissipation structure with strong heat dissipation capability, such as fins, is required. In the present embodiment, only the corresponding metal heat sink 190 is needed to effectively dissipate the heat generated by the pfc transistor 120 and the bridge rectifier 130 of the present embodiment.

Referring to fig. 1, in the present embodiment, the circuit board 110 is divided into a first region 117, a second region 118 and a third region 119 in the length direction D1 of the circuit board 110. It should be noted that, in other embodiments, the first region 117, the second region 118, and the third region 119 may also be unequal in the length direction D1 of the circuit board 110, as long as the difference between the three regions is not too large, for example, the length difference does not exceed 10%, and the invention is not limited thereto.

In the present embodiment, as shown in fig. 1, the power factor correction inductor 140 and the capacitor 150 are located in the second region 118 of the circuit board 110. The power factor correction inductor 140 is located close to the first long side 112, and the capacitor 150 and the power factor correction inductor 140 are disposed on the circuit board 110 side by side along the width direction D2 of the circuit board 110. Of course, in another embodiment not shown, the capacitor 150 may be located close to the first long side 112, and the capacitor 150 and the power factor correction inductor 140 are also disposed on the circuit board 110 side by side along the width direction D2 of the circuit board 110. In short, the positions of the power factor correction inductor 140 and the capacitor 150 in the width direction D2 can be reversed, and the invention is not limited thereto. In addition, the ratio of the length L150 occupied by the projection of the power factor correction inductor 140 and the capacitor 150 to the circuit board 110 to the length L110 of the circuit board 110 in the embodiment is between 0.2 and 0.4. Thus, the length L110 of the circuit board 110 can be greatly reduced, so that the overall size of the adapter power supply 100 is reduced.

Further, in the present embodiment, the power factor correction inductor 140 further has a first long axis 142. The capacitor 150 also has a second major axis 152. Moreover, the first long axis 142 of the power factor correction inductor 140 is parallel to the first long axis 112, and the second long axis 152 of the capacitor 150 is parallel to the first long axis 142 of the power factor correction inductor 140. In detail, the distance d3 between the first long axis 142 of the power factor correction inductor 140 and the second long axis 152 of the capacitor 150 is between 20 mm and 23 mm. That is, the distance D3 between the power factor correction inductor 140 and the capacitor 150 in the width direction D2 is not too far away, so as to avoid increasing the width W110 of the circuit board 110. In other words, the power factor correction inductor 140 and the capacitor 150 of the present embodiment are respectively disposed in parallel and side by side along the first long axis 142 and the second long axis 152 in the width direction D2, and the distances between the two are close. Thus, the area utilization rate of the circuit board 110 of the present embodiment can be improved.

In addition, in the present embodiment, the adapter power supply 100 further includes an input plug 170 and an output end 180, the input plug 170 is disposed in the first region 117 of the circuit board 110, and the output end 180 is disposed in the third region 119 of the circuit board 110. Of course, in other embodiments not shown, the actual positions of the input plug 170 and the output end 180 are not necessarily configured as shown in fig. 1, and the present invention does not limit the forms of the input plug 170 and the output end 180.

On the other hand, in the present embodiment, the transformer 160 is disposed at the third region 119 of the circuit board 110 and is located beside the power factor correction inductor 140 and the capacitor 150. In detail, as shown in fig. 1, a first distance d1 is formed between a center of symmetry 160a of the transformer 160 and a center of symmetry 140a of the power factor correction inductor 140. The center of symmetry 160a of the transformer 160 is a second distance d2 from the center of symmetry 150a of the capacitor 150. Furthermore, the first distance d1 differs from the second distance d2 by no more than 5 millimeters. In short, the transformer 160 of the present embodiment is disposed in the third region 119 of the circuit board 110, and is adjacent to the power factor correction inductor 140 and the capacitor 150. Also, the first distance d1 between the transformer 160 and the power factor correction inductor 140 and the second distance d2 between the transformer 160 and the capacitor 150 are about the same. Thus, the transformer 160, the power factor correction inductor 140 and the capacitor 150 can be arranged closely, and the area utilization of the circuit board 110 can be increased.

It should be noted that, in general, an inductor belongs to an electromagnetic induction component, and its inductance value is related to the size and type of its magnetic conductive member (the magnetic core 144 in fig. 2). The inductance is proportional to the magnetic permeability of the magnetic conductive member, the square of the number of turns of the coil winding, and the sectional area of the equivalent magnetic path, and inversely proportional to the length of the equivalent magnetic path. It should be noted that, in the embodiment, the magnetic conduction member is, for example, the magnetic core 144 (fig. 2), but the invention does not limit the type and material of the magnetic conduction member. Based on the above premise, in the embodiment, how to change the shape of the magnetic core 144 to increase the sectional area of the equivalent magnetic path and reduce the length of the equivalent magnetic path without occupying too much area of the circuit board 110 will be described, so that the power factor correction inductor 140 of the embodiment can use better space utilization.

Fig. 2 is a schematic diagram of the power factor correction inductor of the adapter power supply of fig. 1 shown disassembled. Fig. 3 is a top view of the core of the power factor correction inductor of fig. 2. Referring to fig. 2 and 3, in the present embodiment, the power factor correction inductor 140 includes two magnetic cores 144 and a bracket 146 for winding a coil (not shown). Bracket 146 is assembled between cores 144. Each core 144 includes a central pillar 1441 and two arm portions 1443 located at two sides of the central pillar 1441, and each arm portion 1443 has an arc-shaped outer contour. When the two cores 144 are combined together, the coil is adapted to be located in a space between the two arm portions 1443 and the center leg 1441. The area a1 of a cross section 1441a of the center leg 1441 is the same as the sum a2 of the cross sections of the two arm portions 1443. Further, a distance d4 between the center of the center pillar 1441 and the outer edge of each arm portion 1443 is between 15 mm and 17 mm.

Compared with the conventional magnetic core having a shape close to a long rectangle and a longer length, the magnetic core 144 of the present embodiment reduces the distance between the two arm portions 1443, and makes the two arm portions 1443 have a sufficient area by extending the two arm portions 1443 obliquely upward and downward to resemble two opposite arc shapes, i.e., the total cross-sectional area a2 can be the same as or close to the area a1 of the cross-sectional surface 1441a of the center pillar 1441 of the magnetic core 144 even if the shape is changed. In practice, when the angle θ formed by the connection of the two ends of each arm 1443 of the magnetic core 144 to the axis of the center pillar 1441 is between 85 ° and 90 °, the size of the magnetic core 144 in the width direction can be kept small, and the total cross-sectional area a2 can be the same as or close to the area a1 of the cross-sectional area 1441a of the center pillar 1441 of the magnetic core 144.

In addition, compared to the conventional magnetic core that has a long and narrow rectangle shape, in the embodiment, the ratio of the width W144 to the length L144 of the circumscribed rectangle shape of the magnetic core 144 is between 0.6 and 0.65 due to the reduced distance between the two arm portions 1443 of the magnetic core 144. Based on this design, the length L144 of the circumscribed rectangle of the magnetic core 144 of the present embodiment is shorter than the length of the conventional magnetic core, so that the ratio of the width W144 to the length L144 is larger. Thus, the power factor correction inductor 140 of the present embodiment significantly reduces the length of the circuit board 110. Thus, the dimension of the circuit board 110 in the length direction can be effectively reduced.

In addition, in the present embodiment, the cross section 1441a of the center pillar 1441 takes the shape of a circle with a portion cut off. In detail, the center pillar 1441 of the present embodiment has a shape with a circular truncated portion, because in the present embodiment, the magnetic flux of the magnetic core 144 depends on the smaller of the area a1 of the cross section 1441a of the center pillar 1441 and the sum a2 of the cross-sectional areas of the two arm portions 1443. In short, if the cross section 1441a of the center pillar 1441 of the present embodiment is a complete circle (not shown), the area a1 is larger than the sum a2 of the cross sections of the two arm portions 1443, however, the magnetic flux still depends on the sum a2 of the cross sections of the two arm portions 1443. Therefore, in the present embodiment, the cross section 1441a of the center pillar 1441 is partially cut to avoid consuming excessive space and wasting material.

Of course, in other embodiments not shown, the cross section 1441a of the center pillar 1441 is designed to have an area close to the sum a2 of the cross sectional areas of the two arm portions 1443, and the shape of the cross section 1441a of the center pillar 1441 is not limited thereto. Further, even if a part of the cross section 1441a of the center leg 1441 is not cut, the magnetic flux of the core 144 is not affected. Therefore, the present invention is not limited thereto.

It should be noted that the adapter power supply 100 of the present embodiment has a length of 140.1 mm, a width of 65.1 mm, and a thickness of 25.4 mm, for example. Older adapter power supplies are sized to be about 151.3 mm long, 75.6 mm wide and 25.4 mm thick. Therefore, in the case where the thickness of the adapter power supply 100 of the present embodiment is the same as that of the conventional adapter power supply, the adapter power supply 100 of the present embodiment is reduced by about 20% in size. Further, assuming that the power of the adapter power supply 100 of the present embodiment and the power of the legacy adapter power supply are both 180W, the power density of the adapter power supply 100 of the present embodiment is about 12.7(W/m3), and the power density of the legacy adapter power supply is 10.15(W/m 3). In short, the adapter power supply 100 of the present embodiment provides an increase in power density of approximately 25% over older adapter power supplies.

In addition, it should be noted that, in other embodiments, the detailed size of the adapter power supply 100 of the present embodiment may have a slight error, and the power density of the adapter power supply 100 are only examples, and the detailed size, the power and the power density of the adapter power supply 100 are not limited in the present invention.

In summary, the power factor correction inductor and the capacitor of the adapter power supply of the present invention are respectively arranged side by side along the width direction of the circuit board. Therefore, the long edge of the circuit board can be shortened, and the whole volume of the adapter power supply is saved. In addition, the bridge rectifier and the power factor correction inductor are respectively arranged beside the first long side and the second long side which are opposite. Therefore, high heat energy generated by the bridge rectifier and the power factor correction inductor can be dissipated from two opposite sides in a dispersing manner, no extra heat dissipation component is needed to assist heat dissipation, and the overall size of the adapter power supply is further reduced.

The above disclosure is only a preferred embodiment of the present invention, and should not be taken as limiting the scope of the invention, which is defined by the appended claims.

Claims

1. An adapter power supply, comprising:

the circuit board is provided with a first long edge and a second long edge which are parallel to each other;

a power factor correction transistor configured on the circuit board and close to the first long side;

the bridge rectifier is configured on the circuit board and is close to the second long edge;

the power factor correction inductor is configured on the circuit board and is provided with a first long shaft, and the first long shaft is parallel to the first long side;

a capacitor disposed on the circuit board along a width direction of the circuit board, the capacitor having a second long axis, the first long axis of the power factor correction inductor being parallel to the second long axis of the capacitor; and

and the transformer is configured on the circuit board and is positioned beside the power factor correction inductor and the capacitor.

2. The adapter power supply of claim 1, wherein a distance between the first major axis of the power factor correcting inductance and the second major axis of the capacitance is between 20 millimeters and 23 millimeters.

3. The adapter power supply of claim 1 wherein the ratio of the length occupied by the projection of the power factor correction inductance and the capacitance onto the circuit board to the length of the circuit board is between 0.2 and 0.4.

4. The adapter power supply of claim 1 wherein said circuit board is divided lengthwise into a first region, a second region and a third region equally divided, said power factor correction inductor and said capacitor being located in said second region of said circuit board.

5. The adapter power supply of claim 4 further comprising an input plug located in said first region of said circuit board and said transformer is located in said third region of said circuit board.

6. The adapter power supply of claim 1 wherein said power factor correcting inductor comprises a magnetic core, said magnetic core comprising a center post and two arm portions on opposite sides of said center post, each of said arm portions having an arcuate outer profile.

7. The adapter power supply of claim 6, wherein a distance between a center of the center post and an outer edge of each of the arm portions is between 15 mm and 17 mm.

8. The adapter power supply of claim 6, wherein the angle formed by the connection of the two ends of each arm portion to the center axis of the center pillar is between 85 ° and 90 °.

9. The adapter power supply of claim 6, wherein a cross-section of said leg has a shape with a circular cut-away portion, and the area of said cross-section of said leg is the same as the sum of the cross-sectional areas of said arms.

10. The adapter power supply of claim 6 wherein the ratio of the width to the length of the circumscribed rectangle of said magnetic core is between 0.6 and 0.65.

11. The adapter power supply of claim 1, wherein said transformer is located a first distance from said power factor correction inductor and a second distance from said capacitor, said first distance and said second distance differing by no more than 5 millimeters.