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Unread 15-12-2013, 13:00
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Re: MicroControllers at competitions

Quote:
Originally Posted by yash101 View Post
To increase the 12 bit resolution, I want to decrease the vRef voltage to something like 1v or .1 v, etc.
As someone who designs ADCs for a living, I strongly recommend against using a Vref less than 1v. At 1volt each count of yor ADC is already 25uv and noise of a CMOS amplifier is about 10uV. The best answer is to use a resistor that gives you a voltage that matches the input range of your ADC. I still think the suppy wire is in the right range. The key is to use a high impedance sense circuit with a Kelvin connection in parallel with the supply routing to the speed controller so a not to influence the system performance.