Intrinsic response for analog module testing using an analog testability bus

A parasitic effect removal methodology is proposed to handle the large parasitic effects in analog testability buses. The removal is done by an on-chip test generation technique and an intrinsic response extraction algorithm. On-chip test generation creates test signals on-chip to avoid the parasitic effects of the test application bus. The intrinisic response extraction cross-checks and cancels the parasitic effects of both test application and response observation paths. The tests using both SPICE simulation and MNABST-1 P1149.4 test chip reveal that the proposed algorithm can not only remove the parasitic effects of the test buses but also tolerate test signal variations. Furthermore, it is robust enough to handle loud environmental noise and the nonlinearity of the switching devices.