2results about How to "Avoid potential difference" patented technology

The invention relates to the technical field of semiconductor devices, and discloses a wide bandgap power semiconductor device and a preparation method thereof. The method comprises: providing a substrate layer of a first conductivity type; forming a first doped region which is deep into the substrate layer and comprises a plurality of doped layers which are sequentially nested from outside to inside, wherein the doping concentrations of the plurality of doped layers are sequentially increased from outside to inside; forming a second doped region in the doped layer on the innermost side of the first doped region; forming an isolation layer on the first surface; forming a control electrode on the isolation layer; forming a first electrode on the first surface; a second electrode is formed on the second surface of the substrate layer. According to the invention, the first doped region which is located between the substrate layer and the second doped region and has the doping concentration gradually increased from outside to inside is formed through a mode of multiple times of ion implantation, so that transverse electric field constraint is constructed, transverse depletion of a channel region and a short channel effect under the condition of large voltage are inhibited, the channel width is reduced, and the performance of the device is improved. And the device performance and reliability are improved.

The utility model provides a kind of tubular motor mechanical resistance rebound control circuit, including circuit board and motor, and is equipped with main control module, power module, motor drive module on circuit board, motor drive module includes motor interface, and the middle shaft of motor is equipped with bump block, and microswitch matched with bump block is set on circuit board, and the trigger signal of microswitch is output by motor interface, and power module is for motor, main control module and motor drive module power supply, still include resistance detection filter circuit, resistance detection filter circuit includes diode D1 and photoelectric coupler OP1, the positive pole of diode D1 is connected with the trigger signal output by motor interface, and the negative pole of diode D1 is connected with the input end of photoelectric coupler OP1 with RC filter circuit, the collector of the output end of photoelectric coupler OP1 is connected with the output end of power module by pull-up resistor R4, the collector of the output end of photoelectric coupler OP1 is connected with the signal input end of main control module, and the emitter of the output end of photoelectric coupler OP1 is grounded.