ELECTRONIC CONTROL UNIT

• US 20110013365A1
• Filed: 07/13/2010
• Published: 01/20/2011
• Est. Priority Date: 07/16/2009
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: OOTA, Shinsuke
• Granted Patent: US 8,355,254 B2
• Time in Patent Office: Days
• US Class Current: 361/707
• CPC Class Codes: B62D 5/0406 including housing for electronic control unit
• CPC Class Codes: H01L 25/115 the devices being arranged next to each other
• CPC Class Codes: H01L 25/16 the devices being of types provided for in two or more different main groups of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. forming hybrid circuits
• 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: H02K 11/33 Drive circuits, e.g. power electronics H02K11/38 takes precedence
• CPC Class Codes: H05K 7/20463 Filling compound, e.g. potted resin
• CPC Class Codes: H05K 7/20854 Heat transfer by conduction from internal heat source to heat radiating structure H05K7/20863 takes precedence

Abstract

An electronic control unit includes a circuit board, multiple circuit patterns, multiple semiconductor devices, multiple leads, and at least one thermal-conduction limiting portion. Each of the semiconductor devices is installed to the corresponding circuit pattern formed on the circuit board. Each of the leads electrically and mechanically connects each of the semiconductor devices to the corresponding circuit pattern. The thermal-conduction limiting portion, which can limit conduction of heat generated from the semiconductor devices, is placed between corresponding two of the circuit patterns.

Claims

1. An electronic control unit comprising:

a circuit board;

a plurality of circuit patterns, which are formed on the circuit board;

a plurality of semiconductor devices, each of which is installed to a corresponding one of the plurality of circuit patterns;

a plurality of leads, each of which electrically and mechanically connects between the corresponding one of the plurality of circuit patterns and a corresponding one of the plurality of semiconductor devices; and

at least one thermal-conduction limiting portion, which is placed between corresponding two of the plurality of circuit patterns and is adapted to limit conduction of heat, which is generated from at least one of the plurality of semiconductor devices upon operation thereof, between the corresponding two of the plurality of circuit patterns.

2. The electronic control unit according to claim 1, wherein

a corresponding one of the at least one thermal-conduction limiting portion is placed at a location between one of the corresponding two of the plurality of circuit patterns and a corresponding one of the plurality of leads, which is connected to the semiconductor device that is installed to the other one of the corresponding two of the plurality of circuit patterns.

3. The electronic control unit according to claim 1, wherein

two of the plurality of semiconductor devices, which are configured to be energized simultaneously, are placed obliquely on the circuit board.

4. The electronic control unit according to claim 1, wherein

the thermal-conduction limiting portion includes a groove portion which is dented in a thickness direction of the circuit board.

5. The electronic control unit according to claim 4, wherein

the thermal-conduction limiting portion includes a first low thermal-conductive layer having low thermal conductivity in the groove portion.

6. The electronic control unit according to claim 1, wherein

the plurality of semiconductor devices includes first to fourth semiconductor devices,

the first and second semiconductor devices, which are configured to be energized simultaneously, are placed on a first surface of the circuit board, and

the third and fourth semiconductor devices, which are configured to be energized simultaneously, are placed on a second surface of the circuit board, which is opposite from the first surface of the circuit board.

7. The electronic control unit according to claim 1, further comprising

a thermal conducting path means for conducting the heat, which is generated from the at least one of the plurality of semiconductor devices, wherein

the thermal conducting path means is formed in the circuit board and on at least one of a first surface of the circuit board and a second surface of the circuit board, which is opposite from the first surface of the circuit board.

8. The electronic control unit according to claim 7, wherein

the thermal conducting path means includes a through hole that communicates between the first surface and the second surface of the circuit board, and

an end portion of the through hole is connected to an adjacent one of the plurality of circuit patterns.

9. The electronic control unit according to claim 1, wherein

the at least one of the plurality of semiconductor devices includes a low thermal-conductive member having low thermal conductivity at a side of the circuit board.

10. The electronic control unit according to claim 1, wherein

one of the plurality of leads, which is connected to the corresponding one of the plurality of semiconductor devices, extends to a location, which is on a side of the corresponding semiconductor device where the circuit board is located, so that a space is defined between the circuit board and the corresponding semiconductor devices.

11. The electronic control unit according to claim 1, further comprising

a second low thermal-conductive layer in the circuit board, wherein

at least one of the plurality of semiconductor devices is placed on a first surface of the circuit board,

at least another one of the plurality of semiconductor devices is placed on a second surface of the circuit board, which is opposite from the first surface of the circuit board, and

the second low thermal-conductive layer is adapted to limit conduction of heat, which is generated from the plurality of semiconductor devices placed on the first surface and the second surface of the circuit board.

12. The electronic control unit according to claim 11, wherein

the second low thermal-conductive layer extends along an extending direction of the circuit board.

13. The electronic control unit according to claim 1, wherein

the plurality of semiconductor devices includes first and second semiconductor devices,

the first semiconductor device is placed on a first surface of the circuit board,

the second semiconductor device is placed on a second surface of the circuit board, which is opposite from the first surface of the circuit board, and

the second semiconductor device is placed away from a location directly below the first semiconductor device.

14. The electronic control unit according to claim 7, wherein

the thermal conducting path means is placed directly below the at least one of the plurality of semiconductor devices, which is placed on the at least one of the first surface and the second surface of the circuit board.

15. The electronic control unit according to claim 8, further comprising

an inner layer pattern formed in the circuit board, wherein

the thermal conducting path means includes a first high thermal-conductive layer between the inner layer pattern and the adjacent one of the plurality of circuit patterns formed on at least one of the first surface and the second surface of the circuit board.

16. The electronic control unit according to claim 8, wherein

the thermal conducting path means includes a second high thermal-conductive layer in the through hole.

17. The electronic control unit according to claim 1, further comprising:

a heat releasing gel; and

a case for protecting the plurality of semiconductor devices, wherein

the heat releasing gel is placed between the plurality of semiconductor devices and the case to conduct the heat, which is generated from the at least one of the plurality of semiconductor devices, to the case.

18. The electronic control unit according to claim 17, wherein

the case has a projection that projects to a side of the circuit board, and

the projection is located between corresponding two of the plurality of semiconductor devices.

19. The electronic control unit according to claim 17, wherein

the heat releasing gel is placed on a first surface of the circuit board and a second surface of the circuit board, which is opposite from the first surface of the circuit board.

20. The electronic control unit according to claim 17, wherein

the case is made of an aluminum die-casting product.

21. The electronic control unit according to claim 17, wherein

the heat releasing gel is placed on each of the plurality of semiconductor devices.

22. The electronic control unit according to claim 17, wherein

the case is made of high thermal-conductive resin.

23. The electronic control unit according to claim 17, further comprising

a metal plate integrally formed with the case, wherein

one side surface of the metal plate is exposed to a side of the plurality of semiconductor devices.

24. The electronic control unit according to claim 23, wherein

the metal plate surrounds top surfaces and side surfaces of the plurality of semiconductor devices.

25. The electronic control unit according to claim 23, wherein

the metal plate is placed on each of the plurality of semiconductor devices.

26. The electronic control unit according to claim 23, wherein

an end portion of the metal plate is exposed to an outside of the case.

27. The electronic control unit according to claim 23, wherein

the other side surface of the metal plate is exposed to an opposite side of the plurality of semiconductor devices.

28. The electronic control unit according to claim 23, wherein

at least one of the plurality of semiconductor devices is placed on a first surface of the circuit board,

at least another one of the plurality of semiconductor devices is placed on a second surface of the circuit board, which is opposite from the first surface of the circuit board, and

the metal plate surrounds top surfaces and side surfaces of the plurality of semiconductor devices placed on the first surface and the second surface of the circuit board.