摘要
提出了一种应用于LED驱动器的过温保护电路。该电路的温度检测模块通过调节电流镜两条支路上的电阻比值来提高温度系数,输出级采用共源共栅结构,具有温度系数高、受工艺参数变化影响小、电压稳定好等优点。基于CSMC 0.5μm CMOS工艺,采用Hspice软件对电路进行仿真,结果表明,温度检测模块的工作范围为-45℃-135℃,CTAT输出电压线性度良好,最大偏差小于2%。当电源电压为5V时,负温度系数达到11.2mV/℃,温度感应转变时间小于20ns;该过温保护电路能较好地抑制电源电压波动引起的阈值点漂移,其漂移系数仿真值小于2.5℃/V。
An over-temperature protection circuit for LED（ Light Emitting Diode） driving was proposed, which featured high temperature coefficient by adjusting the resistors＇ ratio of two branches in a current mirror structure. The output stage was in a cascode （vertical cascode） configuration to suppress variations induced by processing parameters or voltage fluctuations. Based on 0.5 μm CMOS model provided by CSMC, Hspice simulations results showed that the temperature detection range was --45 ℃- 135 ℃, the linearity of CTAT（Complementary To Absolute Temperature） output voltage was good, and its maximum deviation was 2%. Also the proposed over-temperature protection circuit owned a negative coefficient of 11.2 mV/℃ @5 V, a temperature detection time of less than 20 ns, and a threshold drift coefficient of less than 2.5 ℃/V due to the variation of voltage supply.
出处
《微电子学》
CAS
CSCD
北大核心
2015年第5期652-656,共5页
Microelectronics
关键词
温度检测
过温保护
LED驱动
Temperature detection
Over temperature protection
LED drive
