Intrinsic response extraction for the removal of the parasitic effects in analog test buses

The removal of the parasitic effects is an emerging issue in the implementation of the IEEE standard 1149.4 analog test buses. For this, this paper defines the intrinsic response and derives an extraction algorithm. The intrinsic response is defined as the response of the circuit being tested by an ideal input signal without the parasitic effect. A deconvolution process is proposed to extract the intrinsic response from the response contaminated by the parasitic effects. The test results using SPICE simulation data show that the intrinsic responses remain the same regardless of the differences in the parasitic effects and the variations in the test signals. The proposed methodology is further tested in the real measurement using the MNABST-1 test chip designed by Matsushita/Panasonic and provided by 1149.4 Working Group. The test results show that the intrinsic response has an improvement of 15.4 dB in signal-to-noise ratio as compared to the direct measurement. It also extends the test frequency range by an order of magnitude. Both tests reassert that the intrinsic response is independent of parasitic effects and input signal variation. They also show that the proposed extraction algorithm is robust enough to handle not only the parasitic effects but also the noise in the real measurement environment.