A systematic procedure for generation and design of parasitic insensitive SC biquads

A systematic method is presented for the generation and design of stray-insensitive switched capacitor (SC) biquads. To this end, the parasitic insensitivity conditions reported earlier in the literature are exploited leading to the general switching scheme that guarantees stray insensitivity. This scheme, in turn, yields the general configuration for a parasitic insensitive SC biquad. Then, following a systematic and exhaustive procedure, 23 new general biquads are obtained, some of which allow canonic designs. The 5 biquads reported so far in the literature are also derived in the process. All networks are input/output compatible with each other and, therefore, can be easily interconnected. Design equations are provided for all the circuits. Possibilities of design improvement using the new biquads are also indicated.