Light responsive semiconductor switch with shorted load protection
US6339236B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 27, 2000 |
| Grant date | Jan 15, 2002 |
| Priority date | — |
| Expiry date | Sep 27, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K3/356
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An improved light responsive semiconductor switch with shorted load protection capable of successfully interrupting a load overcurrent. The switch is includes an output transistor which is triggered by a photovoltaic element to connect a load to a power source thereof, and an overcurrent sensor which provides an overcurrent signal upon seeing an overcurrent condition in the load. A shunt transistor is connected in series with a current limiting resistive element across the photovoltaic element to define a shunt path of flowing the current from the photovoltaic element through the current limiting resistive element away from the output transistor. A latch circuit is included to be energized by the photovoltaic element and to provide an interruption signal once the overcurrent signal is received and hold the interruption signal. The interruption signal turns on the shunt transistor so as to flow the current from the photovoltaic element through the shunt path, thereby turning off the output transistor for interruption of the overcurrent. The current limiting resistive element is connected in series with the shunt transistor to limit the current from the photovoltaic element when the …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.