Soft start solid state switch
US5015921A · kind A · utility
23Cited by
10References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 17, 1988 |
| Grant date | May 14, 1991 |
| Priority date | — |
| Expiry date | Mar 17, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/07
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The junction temperature rise of a power MOSFET serially connected to a lamp whose resistance nonlinearly increases during turn-on is moderated by the use of control circuitry which initially sets up a relatively low essentially constant current flow through the lamp and transistor and then automatically after the lamp resistance reaches a preselected level, the lamp is allowed to draw significantly more current. The size and therefore cost of the power MOSFET is reduced significantly because the magnitude of the current spike generated by turning on the lamp is significantly reduced the use of the novel control circuitry.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.