一种应用于光伏MPPT控制的高精度亚阈区电流比较器

High precision subthreshold current comparator with appling to PV MPPT control

为满足光伏发电最大功率点跟踪技术对电流比较器响应速度、功耗和比较器精度的要求,提出了一种工作在亚阈区、采用正反馈环电路结构、同时实行动态SR(slew radio)增强技术的方法,减小了电流比较器输入节点的时间常数,降低了电流比较器比较点电流偏移值,提高了亚阈区工作模式的电流比较器的精度。改进的电流比较器通过Simc 180 nm工艺仿真设计,在工作频率为1 MHz、参考电流为40 nA时,比较点电流精度可达到0.6 nA。

To meet requirements of the photovoltaic（PV） maximum power point tracking technology to current comparator response speed, power consumption and accuracy, a positive feedback circuit structure was proposed and the dynamic SR enhancement technology working in subthreshold was used, reducing the time constants of current comparators input nodes and current offset values of the current comparator comparing points, increasing the accuracy of current comparators of subthreshold work mode. Results show that through Simc 180 nm process simulation and design, the current accuracy of comparing point of the improved current comparator achieves 0.6 nA when working frequency is 1 MHz and the reference current is 40 nA.