精确高效的渐变结构片上螺旋电感的电感值分析技术

An Accurate Arithmetic for On-Chip Spiral Inductors with Gradually Changed Metal Width and Space

与传统的金属线宽和间距固定不变的无源片上螺旋电感相比,线宽和间距由外圈到内圈渐变的新型结构电感能有效提高电感品质因子.这种新结构电感的出现使得Jenei等人提出的闭合电感公式已不再适用于其电感值的计算,而改进的Wheeler公式计算误差又较大.针对这种情况,文中提出了一种以圈为单位分圈迭代求自感,用整体平均法计算互感的平面螺旋电感的电感值计算方法.该算法分析值与HFSS仿真值相比,误差小于3%,与样品测量值相比,误差小于4%.因此该算法具有计算速度快、精度高的特点,能用于渐变结构片上螺旋电感的高效设计,并可缩短设计周期.

Compared with conventional passive inductors with fixed metal width and space, an inductor with gradually changed mental width and space is put forward to improve its quality factor. But it is difficult to get accurate inductance with most published formulas such as Jenei formula for such novel structure inductor. An accurate arithmetic is presented, which gets total self-inductance by adding up each turn＇s self-inductance and gets mutual-inductance from an average approximate formula. The accuracy and effectiveness are verified by HFSS simulation and experiment measurement. The relative error for this arithmetic compared with HFSS is less than 3%, while compared with experiment measurements less than 4%. These show that it is efficient and valuable for the design of such passive spiral inductor.