Electronic ballast with protected analog dimming control interface
US8654485B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 31, 2011 |
| Grant date | Feb 18, 2014 |
| Priority date | — |
| Expiry date | Dec 19, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B47/18
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A control signal interface circuit includes a line voltage protection circuit coupled to first and second input terminals. The protection circuit provides an input DC voltage across the input terminals within a predetermined range (i.e., 0-10 Vdc) and prevents the application of an input line voltage (i.e., 347 Vac) across the input terminals. A first current source circuit is coupled to the protection circuit, an isolation circuit is coupled to the first current source circuit and a second current source circuit is coupled to the isolation circuit. The first and second current source circuits collectively provide a linear output DC voltage with respect to the input DC voltage. At least one of the first and second current source circuits include circuitry wherein the linear conversion of the input DC voltage to the output DC voltage is independent of the temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.