I'm a noob, so sorry for the question. I'm using a Mesmic 2125 (I think), which is an analog G sensor. Range is 0 to 3G. It is very sensative, and the readings from it jump around quite a bit if you do so much as look at it sideways. Can I use an electrolytic capacitor to calm it down? Maybe the better question is, SHOULD I use a elect cap to calm it down? I want it to give quick readings, but not jump around so much. I have a 100uf cap sitting on my desk here, but I want to consult with you guys before I blow it up--- I mean, before I include it in my circuit...
You read the outputs with analogRead( )? Why not filter that in software some. Could be as simple as zero out the 2 lowest bits so only the larger changes show up for example.
Have to read the datasheet, see if the outputs can drive large capacitive loade. Likely a 0.1uF would be better than 100uF, that's like power supply filter size, not signal filter size.
I could, yes. I just thought that maybe it would be better to use a CAP. But as I said, I'm a noob pretty much, so i thought I'd ask.
What you're trying to do is filter the signal. The simplest low pass filter is a series resistor followed by a capacitor. So rather than cripple the sensor by adding a large capacitor to its output, and risk exceeding its max output drive current, try an RC filter (see Low-pass filter - Wikipedia).
Begin with a 1k resistor so you have a reasonably large value to filter the signal, but not so large that you lose ADC accuracy. Then add whatever capacitor you have. Your 100uF capacitor with a 1k resistor will give a filter time constant of 100ms, which equates to a filter cut-off frequency of 1.6Hz. So it'll progressively reduce the amplitude of frequencies above 1.6Hz.
I want it to give quick readings, but not jump around so much.
Keep in mind that filtering the signal, either with filtering components or in software, trades off 'quick readings' with 'slower smoother readings'. This is a trade-off that you will have to deal with.
Keep in mind that filtering the signal, either with filtering components or in software, trades off 'quick readings' with 'slower smoother readings'. This is a trade-off that you will have to deal with
Well yes, but I didn't want to get into high-order filters and the dreaded Nyquist issues. One step at a time 