Safety Regulations and Their Impact on Microcontrollers in Home Appliances

Governing bodies in the United States and Europe have introduced regulations defining safety requirements in the design of home appliances. In Europe, these requirements are defined by IEC60730, and some aspects are covered in the U.S. by UL 1998. The latter focuses strictly on software issues, in contrast to the broader range of home-appliance issues covered by IEC60730. These regulations require the inclusion of features that will avoid failure or at least ensure that any failure in the appliance does not present a safety hazard to the user. Manufacturers of home appliances must therefore consider how their products will be designed to comply with these requirements. As a major supplier of micro-electronics to home appliance manufacturers, NEC Electronics has had to consider the impact of these standards on customers and products using NEC Electronics' 8-, 16- or 32-bit microcontrollers and, as a result, propose possible solutions. This paper will outline some of those solutions.