Un-Grounded

In college, all electronic systems are grounded. Grounding is a fundamental component of all circuit designs.  However, is that always necessary or desirable?

Our thoughts on this subject developed when we became involved in building a device to be installed in a car.  The electrical environment in a modern motor vehicle is extremely harsh.  Todays electrical components are designed to use milli or micro amps of power.  An automobile starter will pull 30 amps  and the inductive kick from an alternator turning off can excede 100 amps. 

In automotive systems with failing components these aberations can be even larger.  Designing a component for this environment, which uses standard grounding concepts, is an invitation for failure.