Single-ended, self-oscillating DC-DC converter for intermittently energized load having V.sub.BE responsive current limit circuit
US4682081A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 4, 1985 |
| Grant date | Jul 21, 1987 |
| Priority date | — |
| Expiry date | Nov 4, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/335
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The converter delivers current to an intermittently energized load and includes a coupled inductor having a primary winding, a secondary winding and a feedback winding. A switching translator is coupled in series with the primary winding of the inductor and switches between conductive and non-conductive states to control the flow of current through the primary winding. A positive drive circuit provides positive bias voltage to the switching transistor. A current limiting circuit senses the base voltage of the switching transistor to measure the primary winding current, removes the positive bias voltage when the primary winding current reaches a predetermined value, and thereby switches the transistor out of the conductive state into the non-conductive state. A negative drive circuit is coupled between the feedback winding and the base of the switching transistor and supplies a constant negative bias voltage to the transistor base as energy is transferred from the inductor into a load. The negative bias voltage remains constant as the voltage across the feedback varies.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.