Self-oscillation type DC-DC converter having a driving transistor connected in parallel to a circuit element for starting a switching element
US5689178A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 16, 1996 |
| Grant date | Nov 18, 1997 |
| Priority date | — |
| Expiry date | Jul 16, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/1563
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention provides a self-oscillation type DC-DC converter that can perform self-oscillating operation without disposing a feedback winding in a choke coil and realizes the high efficiency, small size and low cost by using a MOSFET as a switching element. The self-oscillation type DC-DC converter comprises a switching transistor Q12 being a P-MOSFET; a first PNP type driving transistor Q2, the collector and emitter of which are connected to the gate and source of the switching transistor Q12, respectively and the base of which is connected to the switching transistor Q12 through a feedback circuit 3; and a second NPN type driving transistor Q3, the gate of the switching transistor Q12 being connected to the ground through the collector and emitter of the second driving transistor Q3 and the base of the second driving transistor Q3 being connected to the feedback circuit 3 through a capacitor C4.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.