Design for testability techniques in switched-capacitor circuits

A way to incorporate design for test methodology into switched-capacitor filters is presented. It falls into what is known in digital circuits as a voting-based scheme. The basic architecture uses some additional circuitry for providing extra capabilities for both off- and on-line test. The approach uses a comparison (voting) mechanism to indicate whether or not two copies of a filter element (a biquad, for instance) have a similar response during their actual operation. The design of two examples is included to assess the potential usefulness of this new approach