ABSTRACT
The heart of the product development process is the verification and validation phase. During this time, testing indicates how well the product has been designed. The parts count reliability prediction had indicated whether the design would meet the reliability goal. It indicated what parts of the circuit had the potential for high failure rate. Design and tolerance analysis had indicated whether the correct component was being used and if it had been specified properly. None of these exercises had indicated how well the components would work together, once the device became operational. To obtain this information, the device must be tested both in its intended application environment as well as in the worst case condition.
