Low voltage direct current power supply
US4685046A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 3, 1985 |
| Grant date | Aug 4, 1987 |
| Priority date | — |
| Expiry date | Oct 3, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M7/2176
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A full-wave bridge rectifier has its input connected directly across a 115 volt RMS alternating current line operating at 60 Hz wherein the output of the bridge provides 120 Hz pulsating direct current at 161 peak volts. A pair of transistors, switching on and off in alternating fashion, continuously apply to a low power requirement load only a leading edge portion and a trailing edge portion of each of the 120 Hz direct current pulses. The resultant direct current voltage, e.g. 11.3 peak volts, across the load is thus substantially reduced to a desirable level as compared to the voltage, 161 peak volts, of the pulsating direct current provided at the line driven bridge output. In another embodiment, the function of the transistors is provided by a pair of operational amplifiers which control the switching of a field-effect transistor in series with the load.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.