Designing Microcomputer Systems to Tolerate Noise

As microprocessors continue to move into increasingly hostile applications, such as engine ignition systems, their susceptibility to noise also increases. The traditional approaches of “noise avoidance”, such as filtering, grounding, shielding may not be enough, and a second line of defenses may be needed. The system must be designed to be “noise tolerant” as well. This paper discusses a number of simple, yet effective, noise tolerant design techniques that may be applied to minimize the consequences of noise in microprocessor based systems.