Printed circuit board assembly

• US 6,982,876 B1
• Filed: 09/13/2000
• Issued: 01/03/2006
• Est. Priority Date: 09/13/1999
• Status: Expired due to Term

• Current Assignee: Commergy Technologies Ltd (Texas Instruments, Inc.)
• Original Assignee: Commergy Technologies Ltd (Texas Instruments, Inc.)
• Inventors: Young, George
• Primary Examiner(s): CHERVINSKY, BORIS LEO
• Application Number:
  US10/070,742
• Time in Patent Office: 1,938 Days
• Field of Search: 361/690, 361703-705, 361709-713, 361717-721, 361/752, 361/758, 361/790, 174/16.3, 174/252, 165/80.3, 165/185
• US Class Current: 361/719
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H05K 1/0203 Cooling of mounted components H05K1/0272 takes precedence
• CPC Class Codes: H05K 1/0206 by printed thermal vias
• CPC Class Codes: H05K 1/141 One or more single auxiliary printed circuits mounted on a main printed circuit, e.g. modules, adapters H05K1/142 and H05K1/147 take precedence
• CPC Class Codes: H05K 1/165 incorporating printed inductors
• CPC Class Codes: H05K 1/182 associated with components mounted in the printed circuit board, e.g. insert mounted components [IMC]
• CPC Class Codes: H05K 2201/086 for inductive purposes, e.g. printed inductor with ferrite core
• CPC Class Codes: H05K 2201/09063 Holes or slots in insulating substrate not used for electrical connections
• CPC Class Codes: H05K 2201/1003 Non-printed inductor
• CPC Class Codes: H05K 2201/10166 Transistor
• CPC Class Codes: H05K 2201/10333 Individual female type metallic connector elements
• CPC Class Codes: H05K 2201/10515 Stacked components
• CPC Class Codes: H05K 2201/10545 Related components mounted on both sides of the PCB
• CPC Class Codes: H05K 3/368 parallel to each other H05K3/361 takes precedence

Abstract

A PCB assembly (1) in this case a DC-DC converter comprising a single layer board (2), mounts power semi-conductor devices forming high heat generating components (3) and various cores of magnetic material forming heat dissipating components (4). Tracks of heat conductive coupling material (6) lie above or below each heat generating component (3) and project into one of the heat dissipating components (4) and beside the others. In one embodiment, the heat generating components (3) are housed within a heat dissipating component (3). In another PCB assembly, there is an additional plug-in PCB which may itself carry heat generating components (3) or only heat dissipating components (4). In the latter case, the heat generating components (3) are mounted on the PCB assembly below the additional plug-in PCB.

Claims

1. A printed circuit board (PCB) assembly comprising:

a plurality of components in said PCB assembly having two sets of different thermal properties over an operating range of said PCB assembly;

a first component set having heat generating properties;

a second component set having heat dissipating and magnetic properties;

means for thermally linking said first component set to said second component set whereby heat generated by at least one component from said first component set is dissipated by at least one component from said second component set.

2. The PCB as claimed in claim 1 wherein the thermally linking means comprises a heat conductive coupling material to couple at least one component from said first component set to at least one component from said second component set.

3. The PCB as claimed in claim 2, in which said heat conductive coupling material is in direct contact with one of said components.

4. The PCB as claimed in claim 2, in which said heat conductive coupling material is housed within at least one of said components.

5. The PCB as claimed in claim 2, in which said heat conductive coupling material forms tracks on said board.

6. The PCB as claimed in claim 2, in which said heat conductive coupling material forms pads on said board.

7. The PCB as claimed in claim 2, in which said heat conductive coupling material forms thermal vias with one component on one side of said board and said other component on the opposite side.

8. The PCB as claimed in claim 2, in which said heat conductive coupling material is a conformable thermally conductive material.

9. The PCB as claimed in claim 1, in which said components are in close physical proximity with minimal air gap between them.

10. The PCB as claimed in claim 1, in which said heat-generating component is housed at least partially within said heat-dissipating component.

11. The PCB as claimed in claim 1, in which said heat dissipating component is mounted above the heat generating component.

12. The PCB as claimed in claim 1, in which a magnetic component from said second component set is a separate magnetic surface mount PCB carrying plug-in interconnect legs for mounting on said board.

13. The PCB as claimed in claim 12, in which said surface mount PCB is a multilayer circuit board.

14. The PCB as claimed in claim 12, in which said surface mount PCB forms part of a power converter comprising power semi-conductors on said board below said surface mount PCB and in which a layer of conformable thermally conductive material fills the space between the bottom of said surface mount PCB and said power semi-conductors.

15. The PCB as claimed in claim 1, in which said heat-dissipating component is thermally linked to more than one heat-generating component.

16. The PCB as claimed in claim 1, in which said heat-generating component is thermally linked to more than one heat-dissipating component.

17. The PCB as claimed in claim 1, in which when said heat generating and said dissipating components have different thermal attributes over said PCB operating range, the choice of components for thermal linking is chosen to provide optimum heat transfer over said PCB operating range.

18. A printed circuit board (PCB) assembly comprising:

a plurality of components in said PCB assembly having two sets of different thermal properties over an operating range of said PCB assembly;

a first component set having heat generating properties;

a second component set having heat dissipating and/or magnetic properties, at least one component comprising a magnetic element having a separate magnetic element surface mount PCB carrying plug-in legs for mounting on said board of said PCB assembly;

means for thermally linking said first component set to said second component set whereby heat generated by at least one component from said first component set is dissipated by at least one component from said second component set.

19. The PCB as claimed in claim 18 wherein the thermally linking means comprises a heat conductive coupling material to couple at least one component from said first component set to at least one component from said second component set.

20. The PCB as claimed in claim 18, in which said magnetic element surface mount PCB is a multilayer circuit board.

21. A power converter having a printed circuit board (PCB) assembly comprising:

a plurality of power semi-conductor components in said PCB assembly having two sets of different thermal properties over an operating range of several PCB assembly;

a first component set having heat generating properties;

a second component set having heat dissipating and/or magnetic properties, at least one component comprising a magnetic element having a separate magnetic element surface mount PCT carrying plug-in legs for mounting on said board of said PCB assembly;

means for thermally linking said first component set to said second component set whereby heat generated by at least one component from said first component set is dissipated by at least one component from said second component set.

22. The power converter as claimed in claim 21 wherein the thermally linking means comprises a heat conductive coupling material to couple at least one component from said first component set to at least one component from said second component set.

23. The power converter as claimed in claim 21, in which said surface mount PCB is arranged above said semi-conductor elements.

24. The power converter as claimed in claim 21, in which a layer of conformable thermally conductive material fills the space between the bottom of said surface mount PCB and said power semi-conductors.