Drive circuit for N-channel power MOS transistors of push-pull stages
US4727465A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 18, 1986 |
| Grant date | Feb 23, 1988 |
| Priority date | — |
| Expiry date | Aug 18, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/01714
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
This circuit, for reliably driving a load both in DC and AC mode with a low dissipation, comprises a pair of MOS power transistors, in a push-pull configuration, and a bootstrap circuit including a bootstrap capacitor placed between the source of the upper MOS transistor and a reference voltage point, through a first switch. A second switch is arranged between the supply line and the gate of the upper MOS transistor, while a third switch is arranged between the gate of the upper MOS transistor and the point common to the first switch and the bootstrap capacitor. During DC operation, the switches are open or closed in order to allow for the connection of the gate of the MOS power transistor to the supply voltage. During AC operation, the switches are controlled thereby, alternately the capacitor is charged at the voltage of the reference voltage point and the upper MOS transistor is held at a gate-to-source voltage sufficient to feed the load.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.