Switching power supply apparatus and luminaire

• US 9,006,974 B2
• Filed: 09/10/2012
• Issued: 04/14/2015
• Est. Priority Date: 11/15/2011
• Status: Expired due to Fees

• Current Assignee: Toshiba Lighting & Technology Corporation (Toshiba Corporation)
• Original Assignee: Toshiba Lighting & Technology Corporation (Toshiba Corporation)
• Inventors: Kitamura, Noriyuki, Takahashi, Yuji, Kawano, Hitoshi, Kumagai, Masatoshi, Saito, Yosuke
• Primary Examiner(s): Hammond, Crystal L
• Application Number:
  US13/608,315
• Publication Number:
  US 20130119860A1
• Time in Patent Office: 946 Days
• Field of Search: None
• US Class Current: 315/51
• CPC Class Codes: H05B 45/30 Driver circuits
• CPC Class Codes: H05B 45/345 Current stabilisation; Maintaining constant current
• CPC Class Codes: H05B 45/3725 Switched mode power supply [SMPS]
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

A switching power supply apparatus according to an embodiment includes a switching element, an inductor, a drive circuit, a mounting substrate, and an insulating substrate. The switching element is connected between a power supply and a lighting load. The inductor is connected in series to the switching element. The drive circuit controls the switching element, converts a voltage supplied from the power supply, and is mounted on the mounting substrate. The insulating substrate is thermally connected to the switching element, and has thermal conductivity higher than the mounting substrate.

Claims

1. A switching power supply apparatus comprising:

a switching element connected between a power supply and a lighting load;

an inductor connected in series to the switching element;

a drive circuit configured to control the switching element and convert a voltage supplied from the power supply;

a mounting substrate on which the drive circuit is mounted; and

an insulating substrate thermally connected to the switching element, and having thermal conductivity higher than the mounting substrate, the insulating substrate being physically separate from the mounting substrate.

2. The apparatus according to claim 1, further comprising a smoothing capacitor provided on the mounting substrate on a second main surface on a side opposite to a first main surface on which the inductor is provided.

3. The apparatus according to claim 2, wherein the insulating substrate is provided on a side of the first main surface.

4. The apparatus according to claim 1, further comprising an AC-DC conversion circuit configured to convert an AC voltage supplied from the power supply to a DC voltage and including a smoothing capacitor provided on the mounting substrate on a second main surface on a side opposite to a first main surface on which the inductor is provided.

5. The apparatus according to claim 1, wherein the switching element is mounted on the insulating substrate.

6. The apparatus according to claim 1, wherein the switching element is mounted on the mounting substrate, and is thermally connected to the insulating substrate via an opening portion provided on the mounting substrate.

7. The apparatus according to claim 1, wherein the switching element is mounted on the mounting substrate, and is thermally connected to the insulating substrate via a conductor.

8. The apparatus according to claim 1, wherein the inductor is a spiral inductor provided on the insulating substrate.

9. The apparatus according to claim 8, further comprising a feedback winding provided on the insulating substrate and magnetically coupled to the inductor.

10. The apparatus according to claim 9, wherein the inductor and feedback winding are provided on an identical plane on the insulating substrate.

11. A luminaire comprising:

a switching power supply apparatus;

a lighting load connected as a load circuit of the switching power supply apparatus; and

a housing configured to accommodate the switching power supply apparatus,

the switching power supply apparatus including;

a switching element connected between a power supply and a lighting load;

an inductor connected in series to the switching element;

a drive circuit configured to control the switching element and convert a voltage supplied from the power supply;

a mounting substrate on which the drive circuit is mounted; and

an insulating substrate thermally connected to the switching element, and having thermal conductivity higher than the mounting substrate, the insulating substrate being physically separate from the mounting substrate.

12. The luminaire according to claim 11, wherein the insulating substrate is thermally connected to the housing.

13. The luminaire according to claim 11, further comprising a smoothing capacitor provided on the mounting substrate on a second main surface on a side opposite to a first main surface on which the inductor is provided.

14. The luminaire according to claim 11, further comprising:

an AC-DC conversion circuit configured to convert an AC voltage supplied from the power supply to a DC voltage and including a smoothing capacitor provided on the mounting substrate on a second main surface on a side opposite to a first main surface on which the inductor is provided.

15. The luminaire according to claim 14, wherein the insulating substrate is provided on the side of the first main surface.

16. The luminaire according to claim 11, wherein the switching element is mounted on the insulating substrate.

17. The luminaire according to claim 11, wherein the switching element is mounted on the mounting substrate, and is thermally connected to the insulating substrate via an opening portion provided on the mounting substrate.

18. The luminaire according to claim 11, wherein the switching element is mounted on the mounting substrate, and is thermally connected to the insulating substrate via a conductor.

19. The luminaire according to claim 11, wherein the inductor is a spiral inductor provided on the insulating substrate.

20. The luminaire according to claim 19, further comprising a feedback winding provided on the insulating substrate and magnetically coupled to the inductor.