AC-DC converter having saw-tooth wave generating circuit in active filter
US5436550A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 14, 1994 |
| Grant date | Jul 25, 1995 |
| Priority date | — |
| Expiry date | Jan 14, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P80/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
This invention provides an AC-DC converter in which the shape and the cost do not increase by a measure for a harmonic distortion in the power factor improved AC-DC converter generating little harmonic distortion. In the AC-DC converter, a control input terminal of a switching transistor of an active filter is connected to an output terminal of a flip-flop, a set input terminal of which is connected to a DC-DC converter to receive a synchronizing pulse signal therefrom. A reset input terminal of the flip-flop is connected to an output terminal of a comparator to receive an OFF-timing signal from the comparator. The comparator determines OFF-timing of the switching transistor by comparing a level voltage with an outout voltage from a saw-tooth wave generating circuit. Thereby since it is not required that an active filter has a multiplier and an an oscillating circuit, its circuit construction is simple and the AC-DC converter in small size and at low cost is realized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.