tailieunhanh - Silicon Carbide Materials Processing and Applications in Electronic Devices Part 15

Tham khảo tài liệu 'silicon carbide materials processing and applications in electronic devices part 15', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 480 Silicon Carbide - Materials Processing and Applications in Electronic Devices The load power for the circuits are obtained from calculation a. Silicon Carbide Schottky diode circuit IRload avg IRload max - IRload min 2 mA - mA 2 mA With Rload value of 55 Q the output power Pout is obtained Pout lRload avg2 x RRload load mA 2 x 55 Q mW b. Silicon Schottky diode circuit IRload avg IRload max - IRload min 2 mA - mA 2 mA With Rload value of 55 Q the output power Pout is obtained Pout lRload avg2 x RRload load mA 2 x 55 Q mW From the calculation the output power Pout generated by SiCS diode circuit is mW and mW for SiS diode circuit. The Pout of SiCS diode is higher by . This is because SiCS diode provides higher output current thus higher efficiency. Fig. 16. Source current Is Current across diode Id and load current IRload Fig. 16 shows the flow of current to the load. This explanation is referred to current divider for diode current Id Is - IRload. The IRioad of SiCS diode is obviously lower than SiCS due to lower IRload. Therefore the SiS diode is proven to have larger power loss. The carbide element in SiCS diode helps in increasing the output current and hence the output power of the circuit. This is due to the fact that SiC has lower reverse recovery current IRR thus lower power losses at the diode during turn-off. Results of reverse recovery current From Fig. 17 it can be seen that there are negative overshoot during turn-off of the diode having IRR below 0A. In this simulation the transient setting is set to be 100 ps. Fig. 18 shows a significant difference of IRR overshoot between SiCS diode and SiS diode. It is observed that the IRR of SiS diode is A whereas mA for SiS diode. The Comparative Assessment of Si Schottky Diode Family in DC-DC Converter 481 advantage of carbide is that the leakage current from anode to cathode is lower due to the