Pareto ANOVA analysis for CMOS 0.18 μm two-stage Op-amp

This paper presents a Pareto ANOVA analysis technique as an alternative way to analyze some selected optimization parameters in two-stage op-amp. Three input parameters and two output parameters based on standard L sub(27)(3 super(13)) in Taguchi method have been chosen in this optimization methodology. The input parameters are selected based on the value of W/L ratio at three transistors which are transistor M8, M9 and M7. Two types of outputs have been aimed to optimize which are power dissipation and gain. This op-amp has been constructed by using CMOS technology 0.18 mu m and the results have been verified by using a Mentor Graphic EldoSpice. From the analysis, it is found that level 16 has been chosen as an optimal combination produced by a Taguchi method. After this, Pareto ANOVA technique will be applied to analyze the effect of selected input parameters in achieving optimum gain and power of the two stage op-amp. The analysis showed that the value of W/L ratio at transistor M9 gives a major impact on power dissipation and value of W/L ratio at transistors M8 and M9 give a major impact on gain. This study also shows that Pareto ANOVA is an easier method to analyze circuit parameters.