Patent attributes
A thermal protection device is for an integrated power MOSFET transistor including an interdigitated array of source regions and drain regions defined in a well region of the monocrystalline silicon substrate, and gate structures overhanging channel regions defined between adjacent source and drain regions. The thermal protection device may include a temperature sensor and a comparator for generating an over temperature flag signal usable for turning off the overheated power transistor. The thermal protection device may sense, in a very accurate manner, the temperature of the power MOS and may include a circuit for forcing a fixed current through a small number of source regions of the interdigitated array separately connected from the other source regions electrically connected in common of the power transistor; and a comparator, integrated on the substrate outside the well region, comparing the source voltage present on the small number of separately connected source regions with a threshold voltage for producing on an output the over temperature flag signal.
