Quote:
Originally Posted by RyanN
Any reason not to use a resistor connected to the 5V Analog Breakout?
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As Bill said, this idea only works in theory. In practice, it is likely to end in tears. I've been down that road many times, each time thinking "this is the time I can get away with it!". That time has never come.
It is bad for two reasons:
1) Inaccurate voltage.
just as Bill said, your output voltage is dependent on your load. Your load is unknown AND variable. Since your output is ratiometric ( the signal is expressed as a fraction of the input voltage ), this is very very very bad.
2) High output impedence.
Output impedence is a measure of the effective resistance of a power rail. Usually it is (much) less than an ohm. This technique would place it in the thousands of ohms. It is an important measure for many reasons, but the most relevant reason here is the ability to deal with switching. (( Bypass capacitors are used to lower it further (for high frequencies))).
You may think that an analog gyro is an analog device, but internally they are chopping in the high tens of kilohertz. A poor output impedence will interfere with this chopping and do "funky things". I'm not positive what, but I'd imagine that you'd end up with a weird offset error.
Bottom Line: Use a regulator. They are cheap and good.