Abstract: Non-drift all-pole active low-pass filters are widely used for their  non-drift characteristics. Based on the definition of statistic sensitivity and theory deduction, an optimum method is put forth for statistic sensitivity of the non-drift all-pole active low-pass filters. Their  feasibility is proved by the  low rank system model.It can be deduced that the system sensitivity is the lowest when all the β_i are equal to one. The decentralization rate of resistance and capacitance is lowered very  much, and the number of the needed elements  is reduced to the half of the formal ones, so as to realize the objects of system simplification. 

Key words: active filter, low-pass filter, statistic sensitivity, parameter simplification