Over-current protection apparatus for transistor
US5621601A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 1994 |
| Grant date | Apr 15, 1997 |
| Priority date | — |
| Expiry date | Sep 28, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D89/60
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The disclosed invention is designed to prevent the oscillation which often occurs in an over-current protection apparatus for an insulated gate controlled transistor. The apparatus improves the response in current detection, to prevent oscillation, and improves protection speed against over-current. This is accomplished by separating the gates of the main transistor and the current detector transistor; by setting a shorter time constant for the gate circuit of the current detector transistor than that of the gate circuit of the main transistor; by feeding the detection signal obtained from the current detecting means which detects the current i of the current detector transistor proportional to the current I flowing through the main transistor, to the control means; and by controlling the gate potentials of both transistors to protect the main transistor from the over-current by feeding the comparison output Sd from the comparator circuit, which compares the voltage of the signal Vd with the reference voltage Vr, to the control circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.