CN102695361A

CN102695361A - Printed circuit board

Info

Publication number: CN102695361A
Application number: CN201110070481XA
Authority: CN
Inventors: 黄宗胜; 陈俊仁; 何敦逸; 周玮洁
Original assignee: Hongfujin Precision Industry Shenzhen Co Ltd; Hon Hai Precision Industry Co Ltd
Current assignee: Hongfujin Precision Industry Shenzhen Co Ltd; Hon Hai Precision Industry Co Ltd
Priority date: 2011-03-23
Filing date: 2011-03-23
Publication date: 2012-09-26

Abstract

The invention provides a printed circuit board which comprises a top layer and a bottom layer. The top layer is provided with a power supply and an electronic component. The power supply is connected with the top layer and the bottom layer through at least one first through hole. A plurality of second through holes are arranged near the electronic element, run through the whole printed circuit board, and are in communication with the top layer and the bottom layer, wherein a center of each second through hole is located on a same straight line, and a line of centers of all second through holes is perpendicular to a current direction of the electronic component. According to the printed circuit board, overhigh temperature caused by excessive current which flows through a second through hole can be avoided.

Description

Printed circuit board (PCB)

Technical field

The present invention relates to a kind of printed circuit board (PCB).

Background technology

Please refer to Fig. 1 and Fig. 2, printed circuit board (PCB) comprises top layer 1, bottom 2, a signals layer 3 and a ground plane 4, and this top layer 1 and bottom 2 are bus plane.This top layer 1 is provided with an electronic component 5, and this electronic component 5 all links to each other with top layer 1 and bottom 2 through two other via hole 5a and 5b.Two row via

hole

6a, 6b, 6c and 9a, 9b, 9c run through whole printed circuit board (PCB) and are communicated with this top layer 1 and bottom 2.One power supply unit 8 that is arranged on the top layer 1 all links to each other with top layer 1 and bottom 2 through two

other via hole

8a and 8b; Be used to electronic component 5 operating current is provided; Wherein one part of current directly flow to this electronic component 5 through top layer 1; Another part electric current will flow to bottom 2 through via

hole

8a, 8b, 6a, 6b and 6c earlier, be back to top layer 1 through three row via

hole

9a, 9b, 9c again, offer this electronic component 5 at last.Because the electric current of bottom 2 can select the minimum path flow of resistance to this electronic component 5, so the time bottom 2 the major part of electric current can flow to top layer 1 by chosen distance electronic component 5 nearest via holes (via hole 9c), thereby arrive electronic component 5.The electric current of via hole 9c of so can causing flowing through is too big, thereby causes this via hole 9c temperature too high, brings unsteadiness for the work of printed circuit board (PCB).

Summary of the invention

In view of above content, the electric current that is necessary to provide a kind of ability to make and flows through via hole is printed circuit board (PCB) comparatively uniformly, and this printed circuit board (PCB) can avoid flowing through electric current of a via hole wherein is excessive.

A kind of printed circuit board (PCB); Comprise top layer and bottom; This top layer is provided with a power supply unit and an electronic component, and this power supply unit all links to each other with bottom with top layer through at least one first via hole, and some second via holes close on said electronic component setting and run through whole printed circuit board (PCB) and be communicated with this top layer and bottom; Being centered close on the same straight line of each second via hole wherein, and the line of centres of all second via holes is vertical with the sense of current of flowing through to said electronic component.

Compare prior art; The form of current vertical of said printed circuit board (PCB) through second via arrangement being become its center line and the electronic component of flowing through avoided a certain second via hole owing to the excessive temperature that causes of the electric current of flowing through is too high so that said some second via holes can be divided equally the electric current of the said electronic component of flowing through.

Description of drawings

Fig. 1 is the sketch map of existing printed circuit board (PCB).

Fig. 2 is the cutaway view of printed circuit board (PCB) among Fig. 1.

Fig. 3 is the sketch map of the preferred embodiments of printed circuit board (PCB) of the present invention.

Fig. 4 is the cutaway view of printed circuit board (PCB) among Fig. 2.

The main element symbol description

Top layer	10
		Bottom	20
Ground plane	30
		Signals layer	40
Via hole	80a、80b、60-65、50a、50b
		Electronic component	50
Power supply unit	80

Following embodiment will combine above-mentioned accompanying drawing to further specify the present invention.

Embodiment

Below in conjunction with accompanying drawing and preferred embodiments the present invention is described in further detail:

Please refer to Fig. 3 and Fig. 4, printed circuit board (PCB) of the present invention comprises a top layer 10, a bottom 20, a ground plane 30 and a signals layer 40, and this top layer 10 and bottom 20 are bus plane.This top layer 10 is provided with an electronic component 50, and said electronic component 50 all links to each other with top layer 10 and bottom 20 through two via hole 50a and 50b.Some via holes (comprising six via hole 60-65 in this execution mode) are insulated from each other and run through whole printed circuit board (PCB), are communicated with this top layer 10 and bottom 20 simultaneously to be electrically connected with this power supply unit 80 and electronic component 50.

One power supply unit 80 that is arranged on the top layer 10 all links to each other with top layer 10 and bottom 20 through two other via

hole

80a and 80b; Be used to electronic component 50 operating current is provided; Wherein one part of current directly flow to this electronic component 50 through top layer 10; Another part electric current will be earlier through via

hole

80a, 80b, 60-62 to bottom 20, be back to top layer 10 through via hole 63-65 and 50a, 50b again, offer this electronic component 50 at last.

This via hole 60-65 is arranged in two row, and wherein via hole 60-62 forms first row, and via hole 63-65 forms secondary series, and via hole 63-65 is centered close on same the straight line, and the line at the center of via hole 63-65 is vertical with the sense of current of flowing through to said electronic component 50.So, the electric current to said electronic component 50 of flowing through is through three via holes (like via hole 63-65), and is excessive with this electric current that reduces a certain via hole of flowing through.

Because the electric current of bottom 20 can select the minimum path flow of resistance to this electronic component 50, so the time bottom 20 the major part of electric current can flow to top layer 10 by chosen distance electronic component 50 nearest via holes (via hole 63-65), thereby arrive electronic component 50.This printed circuit board (PCB) is carried out simulation calculation can obtain the flowing through electric current of via hole to be 3.83 amperes by the electric current that focuses only on a via hole (like via hole 9c) in Fig. 1 circuit board to reduce to the electric current of being divided equally by three via holes (like via hole 63-65) is 3.5 amperes; So; The temperature of via hole (like 9c) is by about 40 degrees centigrade of original about 50 degrees centigrade of temperature that are reduced to three via holes (like via hole 63-65), thereby avoids said via hole (like via hole 9c) upper reaches through excessive electric current.

Said printed circuit board (PCB) has avoided a certain via hole owing to the excessive temperature that causes of the electric current of flowing through is too high through via arrangement being become its center line and flowing through to the vertical form of the sense of current of said electronic component so that each via hole can be divided equally the electric current of flowing through to said electronic component.

Claims

1. printed circuit board (PCB); Comprise top layer and bottom; This top layer is provided with a power supply unit and an electronic component, and this power supply unit all links to each other with bottom with top layer through at least one first via hole, and some second via holes close on said electronic component setting and run through whole printed circuit board (PCB) and be communicated with this top layer and bottom; Being centered close on the same straight line of each second via hole wherein, and the line of centres of all second via holes is vertical with the sense of current of flowing through to said electronic component.

2. printed circuit board (PCB) as claimed in claim 1 is characterized in that: said top layer and bottom are bus plane.