Polarity reversal protection circuit for a final electronic power stage
US6429550B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 27, 2000 |
| Grant date | Aug 6, 2002 |
| Priority date | — |
| Expiry date | Jul 27, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H11/003
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A polarity reversal protective circuit for an electronic power output stage that can be driven via a drive circuit is described. In the case of an incorrect polarization of a supply voltage, power FETs are used in at least one supply terminal to interrupt a connection of the wrongly applied supply voltage to the drive circuit and the power output stage. A definite polarity reversal protection is obtained using a circuit that is improved with respect to cost and space requirement. A single N-channel power FET is looped, with its source-drain path, into the positive supply terminal of the supply voltage. The source terminal of the N-channel power FET is connected with the positive supply terminal. The gate terminal of the N-channel power FET is connected to a collector of a PNP transistor, which is additionally connected to an output of the drive circuit via a current-limiting resistor. An emitter of the PNP transistor is connected—via a diode that is conductive when the supply voltage is wrongly applied—to the positive supply terminal. The base of the PNP transistor is connected—via a base resistor—to a negative (ground) supply terminal of the supply voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.