This paper presents a novel high precision and wide range adjustable LED constant-current drive controller design.Compared with the traditional technique,the conventional mirror resistance is substituted by a MOSFET w...This paper presents a novel high precision and wide range adjustable LED constant-current drive controller design.Compared with the traditional technique,the conventional mirror resistance is substituted by a MOSFET with fixed drain voltage,and a negative feedback amplifier is used to keep all mirror device voltages equal,so that the output current is precise and not affected by the load supply voltage.In addition,the electric property of the mirror MOSFET is optimized by a current subsection mirror（CSM） mechanism,thus ensuring a wide range of output current with high accuracy.A three-channel LED driver chip based on this project is designed and fabricated in the TSMC 0.6μm BCD process with a die area of 1.1×0.7 mm^2.Experimental results show that the proposed LED drive controller works well, and,as expected,the output current can be maintained from 5 to 60 mA.A relative current accuracy error of less than 1%and a maximal relative current matching error of 1.5%are successfully achieved.展开更多
基金supported by the National Ministry Pre-Research Foundation of China(No.9140A08010208DZ0123)the Applied Materials Innovation Foundation of Xi'an,China(No.XA-AM-200817)
文摘This paper presents a novel high precision and wide range adjustable LED constant-current drive controller design.Compared with the traditional technique,the conventional mirror resistance is substituted by a MOSFET with fixed drain voltage,and a negative feedback amplifier is used to keep all mirror device voltages equal,so that the output current is precise and not affected by the load supply voltage.In addition,the electric property of the mirror MOSFET is optimized by a current subsection mirror（CSM） mechanism,thus ensuring a wide range of output current with high accuracy.A three-channel LED driver chip based on this project is designed and fabricated in the TSMC 0.6μm BCD process with a die area of 1.1×0.7 mm^2.Experimental results show that the proposed LED drive controller works well, and,as expected,the output current can be maintained from 5 to 60 mA.A relative current accuracy error of less than 1%and a maximal relative current matching error of 1.5%are successfully achieved.
