Differential Readings upon Reversing Polarity on MEMS Gyroscope

[Free Radical]

Hi, y'all;

This will likely be a simply question for most of you, but I am still something of a neophyte (yes, yes, starting off with the whole education thing in my 30's -- egad!) but if I were to reverse the current running through a MEMS gyroscope, what would be the outcome in the figures it returns -- both digital and analog?

 

[DragonPetter]

I'm not quite sure what you mean by the question.

First, a MEMS chip is designed to run on a specific voltage supply, and so reversing current would probably damage it. There is a "front end" or interface section of these chips that interpret the signal from the MEMS structure and send it out in a format you can easily interface to.

Secondly, most MEMS gyroscopes are vibrating/resonating structures, and so I would guess the current would be AC and go in both positive and negative directions on each cycle. The one I'm thinking of in particular is used in trucks to detect if a truck is tipping over, and this one has 4 wings rotating around an axis at a resonant frequency, and as the angular momentum changes the wings fall out of resonance (Q factor changes). In order for the wings to resonate, you probably want to drive them with an oscillator that will have alternating current in both directions.