Isolation transformer for use in isolated DC-to-DC switching power supply

Patent metadata

Field	Value
Publication number	US-9478351-B2
Application number	US-201313902004-A
Country	US
Kind code	B2
Filing date	May 24, 2013
Priority date	May 24, 2013
Publication date	Oct 25, 2016
Grant date	Oct 25, 2016

Abstract

An isolated DC-to-DC switching power supply includes an isolation transformer having a magnetic core, a first winding around the magnetic core, a first winding-shield around the magnetic core, a second winding-shield within the first winding-shield, and a second winding within the second winding-shield. There is no direct coupling between the first winding and the second winding since the second winding is enclosed within the second winding-shield and the second winding-shield is enclosed within the first winding-shield.

First claim

What is claimed is:

1. An isolated DC-to-DC switching power supply, comprising:
an isolation power transformer including:
a magnetic core;
a first winding around the magnetic core;
a first electrostatic winding-shield around the magnetic core;
a second electrostatic winding-shield within the first electrostatic winding-shield; and
a second winding within the second electrostatic winding-shield,
such that the first winding electrostatically couples to the first electrostatic winding-shield and the second winding electrostatically couples to the second electrostatic winding-shield, such that there is no charge flow between the first electrostatic winding-shield and the second electrostatic winding-shield; and

wherein each of the first winding, the first electrostatic winding-shield, the second electrostatic winding-shield and the second winding are affixed to a printed circuit board.

2. The isolated DC-to-DC switching power supply of claim 1 , wherein the isolation power transformer further includes a double-shielded cable comprising the first electrostatic winding-shield as an outer conductor of the double-shielded cable, the second electrostatic winding-shield as the inner conductor of the double-shielded cable, and the second winding as the center conductor of the double-shielded cable, and the first winding is a wire external to the double electrostatic winding-shielded cable.

3. The isolated DC-to-DC switching power supply of claim 1 , in which the first electrostatic winding-shield is the first electrostatic winding-shield and a part of the first winding.

4. The isolated DC-to-DC switching power supply of claim 2 , in which the first electrostatic winding-shield is the first electrostatic winding-shield and a part of the first winding.

5. The isolated DC-to-DC switching power supply of claim 1 , in which the first electrostatic winding-shield is the first electrostatic winding-shield and all of the first winding.

6. The isolated DC-to-DC switching power supply of claim 2 , in which the first electrostatic winding-shield is the first electrostatic winding-shield and all of the first winding.

7. The isolated DC-to-DC switching power supply of claim 1 , in which the second electrostatic winding-shield is the second electrostatic winding-shield and part of the second winding.

8. The isolated DC-to-DC switching power supply of claim 2 , in which the second electrostatic winding-shield is the second electrostatic winding-shield and part of the second winding.

9. The isolated DC-to-DC switching power supply of claim 1 , in which the second electrostatic winding-shield is the second electrostatic winding-shield and all of the second winding.

10. The isolated DC-to-DC switching power supply of claim 2 , in which the second electrostatic winding-shield is the second electrostatic winding-shield and all of the second winding.

11. The isolated DC-to-DC switching power supply of claim 1 , wherein the isolation power transformer further includes a coaxial cable comprising a first electrostatic winding-shield as an outer conductor of the coaxial cable, and a center conductor is the second electrostatic winding-shield and the second winding, the first winding is a wire external to the coaxial cable.

12. The isolated DC-to-DC switching power supply of claim 1 , wherein the isolation power transformer further includes a coaxial cable in which the outer conductor of the coaxial cable is the first winding and the first electrostatic winding-shield, and a center conductor is the second electrostatic winding-shield and the second winding.

13. The isolation power transformer of claim 2 , wherein a plurality of double-shielded cables are wound in parallel through the magnetic core and connected together to create the first electrostatic winding-shield, the second electrostatic winding-shield, and the second winding.

14. The isolation power transformer of claim 11 , wherein a plurality of coaxial cables are wound in parallel through the magnetic core and connected together to create the first electrostatic winding-shield, the second electrostatic winding-shield, and the second winding.

Assignees

• Keithley Instruments

Inventors

• Goeke Wayne C
• Gibbons John C

Classifications

• H01F2027/2833

  using coaxial cable as wire · CPC title

• H01F27/288

  Shielding · CPC title

• H01F27/362 Primary

  Electricity · mapped topic

• H01F27/363 Primary

  made of electrically conductive material · CPC title

• H01F27/36

  Electric or magnetic shields or screens (movable for varying inductance H01F21/10) · CPC title