一個內建式電流感測之可控電流降壓LED驅動器

Abstract

本論文提出了一個內建式電流感測器，並應用於降壓型LED驅動器上。此內建式電流感測器採用感測電晶體與積分器電路之方法來實現，然後將此電流感測器之感測訊號回授至控制電路，並加上控制輸出平均電流的機制，進而去達到控制輸出電流之目的。本晶片使用TSMC 0.25 1P3M HV CMOS製程，系統操作頻率為1.1MHz，轉換器最大效率為96.6%，電流誤差為±1.7%，晶片佈局面積為1535×1269〖um〗^2。

This thesis presents an architecture of an on-chip current sensor. It is implemented in a LED driver. This sensor has been designed using SenseFET to detect the output current for the feedback control. As a resoult, the output current can be stabilized and the efficiency can be maximized. This chip will be fabricated in TSMC 0.25 1P3M HV CMOS process. The frequency of the system clock is 1.1MHz. The maximum efficiency of the converter is 96.6%. The current error is ±1.7%. The chip area is1535×1269〖um〗^2.