Dissipating heat in an array of circuit components

• US 6,920,046 B2
• Filed: 06/25/2003
• Issued: 07/19/2005
• Est. Priority Date: 06/25/2003
• Status: Expired due to Fees

• Current Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Original Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Inventors: Spryshak, Joseph J.
• Primary Examiner(s): THOMPSON, GREGORY D
• Application Number:
  US10/603,519
• Publication Number:
  US 20040264141A1
• Time in Patent Office: 755 Days
• Field of Search: 165/80.3, 165/185, 361704-710, 361719-720, 362/218, 362/294, 362/373, 362/800
• US Class Current: 361/704
• CPC Class Codes: H05K 1/0206 by printed thermal vias
• CPC Class Codes: H05K 2201/09781 Dummy conductors, i.e. not used for normal transport of current; Dummy electrodes of components
• CPC Class Codes: H05K 2201/10106 Light emitting diode [LED]
• CPC Class Codes: H05K 2203/0191 Using tape or non-metallic foil in a process, e.g. during filling of a hole with conductive paste
• CPC Class Codes: H05K 2203/1572 Processing both sides of a PCB by the same process; Providing a similar arrangement of components on both sides; Making interlayer connections from two sides
• CPC Class Codes: H05K 3/0061 onto a metallic substrate, e.g. a heat sink heat sinks for electric apparatus H05K7/20
• CPC Class Codes: H05K 3/42 Plated through-holes or plated via connections

Abstract

A circuit board assembly with an array of closely spaced circuit components mounted thereon. The board has a pattern of conductive strips on both front and back faces and the strips are connected through the board by thermally conductive vias. The circuit components are mounted on one side of the board and a layer of thermally conductive, double-sided adhesive tape is laid over the conductive strips on both faces of the board. Heat sinks are then applied against the tape on both sides of the board to conduct heat from the board through the tape.

Claims

1. A method of dissipating heat in an array of circuit components comprising:

(a) providing a circuit board having a front and back face with a pattern of electrically conductive strips having a relatively high coefficient of thermal conductivity disposed on each of the front and back face of the board;

(b) disposing a plurality of said components in an array on one of the front and back faces of the board and connecting each of said components to the front and/or back pattern of strips;

(c) applying a layer of tape having a relatively high coefficient of thermal conductivity to each of said front and back faces of the board; and

,

(d) disposing a heat sink in contact with the tape on each of the front and back faces of the board.

2. The method defined in claim 1, wherein said step of disposing circuit components in an array includes disposing a plurality of light emitting diodes (LEDs).

3. The method defined in claim 2, wherein said step of disposing LEDs includes disposing same in equidistant arrangement with respect to said heat sink.

4. The method defined in claim 1, wherein said step of providing a circuit board includes arranging a pattern of electrical leads disposed on the front and back for conducting heat array from each of the circuit components.

5. The method defined in claim 1, wherein said step of providing a circuit board includes providing a relatively thin board formed of flexible material.

6. The method defined in claim 1, wherein said step of disposing a heat sink includes disposing a member having a finned surface.

7. The method defined in claim 1, wherein said step of applying a layer of tape includes applying a tape formed of polymeric film material coated with thermally conductive acrylic adhesive on opposite sides of the tape.

8. The method defined in claim 1, wherein said step of applying a layer of tape includes applying a tape having a thermal conductivity of about 0.4 Watts/meter-K as measured per ASTM D5470.

9. The method defined in claim 1, wherein said step of applying a tape includes applying a double-sided adhesive tape.

10. The method defined in claim 1, wherein said step of disposing a plurality of components includes soldering the leads of the components to said conductive strips.

11. The method defined in claim 1, wherein said step of providing a circuit board includes disposing a plurality of electrically and thermally conductive vias through the board.

12. The method defined in claim 1, wherein the step of disposing a plurality of components includes orienting the board at an angle of about 42°

to the vertical.

13. In combination a circuit board with an array of circuit components comprising:

(a) said circuit board having a front and back face with a pattern of electrically conductive strips having a relatively high coefficient of thermal conductivity disposed on each of the front and back faces of the board;

(b) a plurality of said components disposed in an array of one of said front and back faces of the board with each of the components electrically connected to the conductive strips on the front and/or back faces;

(c) a layer of thermally conductive tape disposed over the conductive strips on each of the front and back faces of the board; and

,

(d) a heat sink disposed against said layer of tape on each of said front and back faces of the board.

14. The combination defined in claim 13, wherein said tape is formed of polymeric film coated with thermally conductive acrylic adhesive on opposite sides of the tape.

15. The combination defined in claim 13, wherein said tape has a thermal conductivity of about 0.4 Watts/meter-K as measured per ASTM D5470.

16. The combination defined in claim 13, wherein said tape comprises a double-sided adhesive tape.

17. The combination defined in claim 13, wherein said circuit board includes a plurality of electrically and thermally conductive vias extending from the front face through the board to the back face.