The schedule was insane, the chip difficult, the physics murky, and the company disorganized. Then they said the magic words "money is no object". I had a break in the schedule with I-Cube, so I said the fateful words "sure".
The component was simple but fiendish; the driver/sensor/filter/interface for a 3 axis fluxgate magnetometer, which would be used to sense the direction of the Earth's magnetic field and provide head orientation information for the VR helmet. Fluxgate magnetometers work by saturating a ferrite toroid with a high current, then looking for the voltage blip caused by the change in the magnetic flux from the Earth through the core. A one gauss change through a tiny winding produces a millivolt blip; we had to digitize three of those blips to about 16 bits precision and 10 bits of accuracy.