Circuit and methodology for supplying pulsed current to a load, such as a light emitting diode
US7746300B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 5, 2006 |
| Grant date | Jun 29, 2010 |
| Priority date | — |
| Expiry date | Apr 29, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B45/39
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A circuit for controlling pulsed current to a load, one application of which is in LED dimmer circuitry, comprises first and second reference nodes for receiving a supply voltage, an input node for receiving a timing signal such as a PWM signal, and a controlled switch coupled between the first and second reference voltage nodes for supplying current to the load. Pull-up circuitry may be coupled between a control electrode of the controlled switch and first reference voltage node, and a pull-down switch coupled between the control electrode and second reference voltage node. A control circuit coupled between the input node and control electrode of the controlled switch is configured to control the controlled switch in response to the timing signal. The circuit may further include a reference voltage source configured for producing a voltage of magnitude independent of supply voltage magnitude. The control circuit is coupled to the reference voltage source and operative to control the controlled switch in response to the timing signal and reference voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.