Switched regulator circuit having an extended duty cycle range
US4652809A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 6, 1986 |
| Grant date | Mar 24, 1987 |
| Priority date | — |
| Expiry date | Jan 6, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/33538
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a DC switching regulator circuit, a circuit to demagnetize the transformer during OFF periods to extend the duty cycle range of the regulator. The regulator uses a transformer in series with an FET switch device to cause the primary transformer current to be switched ON and OFF in response to the power needs of an electrical load connected to the secondary circuit. A first diode, connected to the junction of the primary winding and a series switch, conducts the demagnetizing energy out of the primary circuit into a shunt connected storage capacitor. A second FET switch, operating out of phase with the first switch, allows the storage capacitor to discharge through an inductor back to the unregulated input source. A shunt diode between the inductor and the second FET switch provides a path for the inductor to discharge through when the second switch opens the path between the storage capacitor and the inductor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.