Low cost inverter for EL lamp
US5502357A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 3, 1994 |
| Grant date | Mar 26, 1996 |
| Priority date | — |
| Expiry date | Oct 3, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An EL lamp is driven by a flyback inverter having an inductor connected in series with a first transistor which switches on and off at a high frequency. The junction of the inductor and transistor is connected through a switching diode to an output terminal for connection to an EL lamp. A discharge path, including a second transistor, is coupled to the lamp for removing accumulated charge. The second transistor switches on and off at a low frequency for periodically discharging the electrical charge accumulated on the EL lamp. In accordance with one aspect of the invention, several diodes are connected in series with the switching diode to block waste current during discharge of the EL lamp. In accordance with another aspect of the invention, the switching diode is temporarily by-passed to provide the discharge path for the lamp. In accordance with either aspect of the invention, the inverter can produce alternating current through the lamp by adding a capacitor in series with the lamp.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.