Power conversion module device and power unit using the same
In a power conversion module device of the present invention, a transformer, a primary power element and a secondary power element are mounted on a printed wiring board in surface-to-surface contact therewith, and no control circuit is mounted thereon. In addition to reducing impedance and loss in the wiring, this constitution improves the voltage waveform of the primary power element. Thus, noise reduction can be achieved. Further, because heat can be transferred to the printed wiring board, heat generated from the transformer, the primary power element and the secondary power element can be reduced. The size of the transformer can also be reduced.
1. A power conversion module device comprising:
a printed wiring board;
a transformer mounted on said printed wiring board in surface-to-surface contact therewith;
at least one of a primary power element and a secondary power element mounted on said printed wiring board in surface-to-surface contact therewith; and
an external connection terminal provided on said printed wiring board, said external connection terminal being operable to connect components mounted on said printed wiring board to a control circuit part provided on a separate substrate from said printed wiring board, wherein:
said printed wiring board has a structure of a highly heat radiating board having an insulator and a wiring board unitary with a lead frame bonded to each other; and
a metal plate is bonded to a backside of a surface of said insulator having the lead frame.
2. The power conversion module device of claim 1 , wherein a thickness of said insulator is at least 0.4 mm.
3. The power conversion module device of claim 1 , wherein said insulator is made of an epoxy resin.
4. The power conversion module device of claim 1 , wherein said insulator is made of a ceramic material.
5. The power conversion module device of claim 1 , wherein the lead frame is formed of a copper plate having a thickness of at least 0.3 mm.
6. The power conversion module device of claim 1 , wherein the lead frame is bent to form said external connection terminal of said module.
7. The power conversion module device of claim 1 , wherein a material of the metal plate is aluminum.
8. The power conversion module device of claim 1 , wherein a material of the metal plate is copper.
9. The power conversion module device of claim 1 , wherein said transformer and at least one of said primary power element and said secondary power element are mounted on a single principal surface of said printed wiring board.
10. The power conversion module device of claim 1 , wherein said printed wiring board is composed a single-sided printed wiring board having a pattern formed on one side thereof.
11. The power conversion module device of claim 1 , wherein said printed wiring board is composed of a double-sided printed wiring board having patterns formed on both sides thereof.
12. The power conversion module device of claim 1 , wherein said printed wiring board is composed of a multi-layered printed wiring board.
13. The power conversion module device of claim 1 , wherein at least one of a primary coil and a secondary coil of said transformer is formed of a coil shaped like a thin plate.
14. The power conversion module device of claim 1 , wherein at least one of a primary coil and a secondary coil of said transformer is formed of a three-layered insulated wire.
15. The power conversion module device of claim 1 , wherein at least one of a primary coil and a secondary coil of said transformer is formed by winding a winding wire.
16. The power conversion module device of claim 1 , wherein at least one of a primary coil and a secondary coil of the transformer is formed of a printed board.
17. The power conversion module device of claim 1 , wherein said transformer is mounted on said printed wiring board so that a bottom surface of a magnetic core of said transformer is in contact with said printed wiring board.
18. The power conversion module device of claim 1 , wherein said transformer is disposed between said primary power element and said secondary power element.
19. The power conversion module device of claim 3 , wherein the resin includes mineral filler.
20. The power conversion module device of claim 6 , wherein at least one external connection terminal is operable to form a terminal for connection to the control circuit part.
21. The power conversion module device of claim 13 , wherein the thin-plate coil is formed of a copper plate having a thickness of at least 0.3 mm.
22. The power conversion module device of claim 15 , wherein the winding wire of the coil has a fusion layer.
23. The power conversion module device of claim 16 , wherein a prepreg is inserted between layers of the coil to form a multi-layered printed board coil.
24. The power conversion module device of claim 17 , wherein a pattern is formed on a surface of said printed wiring board facing said magnetic core.
25. The power conversion module device of claim 17 , wherein a heat conductive member is inserted between said magnetic core and said printed wiring board.
26. The power conversion module device of claim 22 , wherein the fusion layer is a type fused by alcohol.