一种应用于LED驱动的新型过温保护电路  

A novel over-temperature protection circuit for LED driver

作　　者：文鑫 冯全源[1] 程简 Wen Xin;Feng Quanyuan;Cheng Jian(Institute of Microelectronics,Southwest Jiaotong University,Chengdu 611756,China;Science&Technology Department of Sichuan Province,Chengdu 610016,China)

机构地区：[1]西南交通大学微电子研究所,四川成都611756 [2]四川省科学技术厅,四川成都610016

出　　处：《电子技术应用》2024年第1期27-30,共4页Application of Electronic Technique

基　　金：国家自然科学基金重点项目(6290012);中央在川高校院所重大科技成果转化项目(2022ZHCG0114)。

摘　　要：基于0.18μm BCD工艺,设计了一种应用于LED驱动的新型过温保护电路。利用基于电流求和的Banba型带隙基准源来产生高低阈值电压,从而消除芯片在过温点附近的振荡现象,同时带隙基准源加入了高阶曲率补偿,提高了过温阈值点的精度。通过Cadence软件对该电路进行了仿真验证。结果表明,在-40℃~150℃的温度变化区间内,高低阈值电压的温度特性好,温度系数为2.9 ppm。当温度高于131.8℃时,能够触发过温保护;当温度低于109.4℃时,电路可恢复正常工作,迟滞量为22.4℃。该过温保护电路精度高,稳定性好,可应用于LED驱动芯片中。In this paper,a new type of over-temperature protection(OTP)circuit for LED driver is designed.It is based on 0.18μm BCD process.In this paper,Banba′s bandgap reference based on current summing is used to generate high and low threshold voltage,to eliminate the oscillation phenomenon near the over-temperature point of the chip.The bandgap reference is added with high-order curvature compensation to improve the accuracy of the over-temperature threshold voltage.The circuit is simulated by Cadence software.The results show that the high and low threshold voltage has good temperature property,the temperature coefficient is 2.9 ppm in a temperature range of-40℃to 150℃.When the temperature is higher than 131.8℃,OTP can be triggered.When the temperature is lower than 109.4℃,the circuit can return to normal operation,and the hysteresis quantity is 22.4℃.The OTP has high precision and stability,and can be applied to LED driver chips.

关 键 词：LED驱动 过温保护 热振荡 

分 类 号：TN433[电子电信—微电子学与固体电子学]