Low-profile planar transformer for use in off-line switching power supplies
US5010314A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 30, 1990 |
| Grant date | Apr 23, 1991 |
| Priority date | — |
| Expiry date | Mar 30, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F2027/2819
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A low-profile planar type transformer having a unique bobbin design and a minimum of other pieces. The transformer is assembled by simply stacking all of the pieces, other than core pieces, in a sandwich-like-laminate and placing two appropriately shaped ferrite core pieces around the stack. In the preferred embodiment, the stack consists of the following layers, in the listed order: (a) a first thin dielectric spacer; (b) a first planar member (e.g., a PC board) containing a first winding; (c) two thin dielectric insulators; (d) a first nylon bobbin member; (e) a second planar member containing a second winding; (f) a third thin dielectric insulator; (g) a third planar member containing a third bobbin member; (h) a second nylon bobbin member; (i) two thin dielectric insulator; (j) a fourth planar member containing a fourth widning, and (k) a seventh thin dielectric insualtor. Two E-shaped ferrite cores are placed around the stack, with the center arm of the "E" going through a hole in the middle of the stack, to magnetically couple the current in the second planar member's windings to the windings of the first and third planar member.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.