Patent ID: 7932133
Filing Date: 2011-04-26
Classification: H01L

Abstract:
1. A method for protecting an electrical circuit load from a high energy pulse including steps connecting a polymeric positive temperature coefficient (PPTC) resistive element in series with the electrical circuit load and an energy source; connecting a reverse breakdown overvoltage energy pulse absorbing semiconductor device as a shunt element between the electrical circuit load and the PPTC resistive element, said semiconductor device having a heat transfer surface sized in relation to, and in direct thermal contact with, the PPTC resistive element; forming the semiconductor device by steps including: receiving the high energy electrical pulse from the energy source into the semiconductor device thereby causing the at least one cell to become a first-level unidirectional conduction region for generating heat and transferring heat to the at least one region and thereupon causing the at least one region to become a second-level bi-directional intrinsic conduction and heat generating region; and transferring the heat from the first-level unidirectional conduction region and from the intrinsic conduction and heat generating region to the PPTC resistive element via the heat transfer surface, thereby accelerating trip of the PPTC resistive element to a high resistance state and disconnecting the electrical circuit load and the semiconductor device from the energy source.