Pulse width modulated driver
US6377131B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 18, 2000 |
| Grant date | Apr 23, 2002 |
| Priority date | — |
| Expiry date | Oct 18, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/145
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A pulse width modulated driver 20 is provided for driving a load 17, such as a halogen bulb, at a reduced voltage level. The driver 20 includes a switch 28 selectively opening and closing to apply a pulse width modulated signal VPWM to a high voltage end of the load 17. The switch 28 operates responsive to a switch control signal VS. The driver 20 further includes a duty cycle control circuit 26 generating the switch control signal VS when an input operational voltage Vo is above a threshold voltage level. Finally, the driver includes an energy storage circuit 24 for storing electrical energy when the switch 28 is open to maintain the input operational voltage Vo above the threshold voltage level. The driver 20 is connected on a high side of the load 17 and does not require a separate line connected to system ground.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.