Symmetry control circuit and method
US5583402A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 31, 1994 |
| Grant date | Dec 10, 1996 |
| Priority date | — |
| Expiry date | Jan 31, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/07
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention provides a method and circuit for controlling the flow of current through a load. In a preferred embodiment, an oscillator generates a pulse signal of constant frequency. A pulse width modulator adjusts the duty cycle of the pulse signal in response to a dimming level signal input indicative of the desired level of current flow through the load. A converter receives the pulse signal as an input and converts it into an AC signal, the frequency of which follows the frequency of the pulse signal and the symmetry of which varies with the duty cycle of the pulse signal. The load is connected into a resonant circuit tuned such that a change in the symmetry of the AC signal changes the level of current flowing through the load.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.