一個內建自我溫度平衡機制之直流升壓型轉換器

Abstract

本論文提出了一個功率電晶體自我溫度平衡機制，並實現於直流升壓型轉換器上，此機制可有效改善功率電晶體溫度分布不均的現象，內嵌的溫度感測器偵測各子功率電晶體之初始溫度，之後於正常操作時再次偵測各顆的操作溫度，經過比較後尋找出溫度上升最高的子功率電晶體，將此電晶體進行閘極脈波調變來降低其責任週期，並可依功率電晶體溫度分佈自我調整擷取之脈波數，達到短暫休息的目的，使最高溫者溫度降低，低溫者溫度些微升高，延長最高溫子功率電晶體之壽命，間接提升功率電晶體串之可靠度。 本晶片使用TSMC 0.25um 1P5M HV CMOS製程，系統操作頻率為1MHz，轉換器最大效能為91.1%，晶片佈局面積為1406x1268um2。

This thesis proposes a DC-DC Boost Converter with self-temperature balancing mechanism for power MOS. The mechanism is able to improve the phenomenon of imbalance temperature distribution of power MOS. The built-in temperature sensor senses initial temperature of each bank. When power MOS is in operation, T Sensor senses current temperature of each bank again, and it will search for the bank of maximum rising temperature after comparing eight times. Then the Gate Modulation Circuit, which is able to adjust the number of pulses taken according to temperature distribution of power MOS, lowers the duty cycle of the max-temperature bank. The mechanism makes the bank with the highest temperature rest for a while, reducing its duty cycle, and improve the reliability of the bank with the highest temperature, which in turn improve the reliability of power MOS array. This chip is fabricated in TSMC 0.25um 1P5M HV CMOS process. The frequency of system clock is 1MHz. The maximum efficiency of the converter is 91.1%. The chip area is1406x1268um2.