ABSTRACT
This chapter reviews the problem of electrostatic discharge (ESD) as it affects wireless sensor network nodes, and the importance of proper electrical, mechanical, and product design in its control. Similar to electromagnetic compatibility (EMC) problems, ESD problems often require a multidisciplinary approach for proper resolution. Unlike most EMC problems, however, ESD problems can be difficult to identify in the field; often, the first indication of an ESD weakness in a design are sporadic reports of “dead” nodes not attributable to other causes, or reports of very specific failure types, such as corruption of certain register contents in a microcontroller. ESD problems are difficult enough to detect in wireless sensor networks designed for consumer and home automation applications, where an ESD event may be instigated by a charged individual, but become even more troublesome in networks for industrial, agricultural, and military applications, many of which operate essentially autonomously, without direct human contact. Lack of human contact may lower the overall failure rate, but can result in a lack of information on the failures that do occur. It is important, therefore, to understand the ESD problem, so that it may be “designed out” of the finished product.
