If a VLSI chip is partitioned into functional units (FU's) and redundant FU's are added, error correcting codes may be employed to increase the yield and/or reliability of the chip. Acceptable testing is defined to be testing the chip with the error corrector functioning, thus obtaining the maximum increase in yield afforded by the error correction. The acceptable testing theorem shows that the use of coding and error correction in conjunction with acceptable testing can significantly increase the yield of VLSI chips without seriously compromising their reliability.

An analog data acquisition system typically consists of an analog multiplexor followed by an analog to digital (A/D) converter. An alternative configuration uses multiple comparators (one per input) followed by a digital multiplexor. If the control functions for A/D conversion are incorporated into a microprocessor, several potentially interesting data acquisition and conversion strategies are available. At first thought, an interrupt-driven conversion process which simultaneously searches all inputs in parallel for a level match appears attractive. However, analysis shows that a sequential conversion of the inputs, one at a time, using the successive approximation algorithm, is usually superior.