Reliability considerations for implantable medical ICs

Implantable medical devices continue to grow in complexity, mirroring the ascent of the semiconductor industry along the Moorepsilas Law curve. Traditionally, implantable applications have taken a fast-follower approach to silicon adoption, using more mature technologies to reduce risk. While commercial manufacturers, in some circumstances, may be able to trade off lifetime requirements for performance, this is decidedly not the case for implantable use, where 10 to 12 year requirements are typical. On the other hand, hardware and software redundancy solutions employed by high reliability avionics, telecommunications, and servers are difficult to implement in a battery-powered device, where current drain restrictions are severe. This paper discusses some of the reliability challenges faced by implantable device manufacturers as the need to provide more sophisticated therapy and diagnostics requires increasingly advanced technologies.