CheapStat for Low Current Measurements
Does anyone have any experience using the CheapStat to measure currents in the 0-50nA range?
I think this range is too low for the cheapstat. In the stock configuration there are two current ragnes +/- 10uA and +/- 50uA. However, I think even the +/-10uA range will be to coarse for your measurements in the 50nA range. It is possible to change the current range by changing a resistor on the PCB - I've put some notes on doing this here http://forum.iorodeo.com/topic/3/dye-sensitized-solar-cell-analysis. You would need to swap out the R12 feedback resistor with somethings larger. I haven't tried decreasing the current range this much myself so I'm not sure how well this will work or what issue you will run into.
@Will-Dickson have you tried decreasing the current range at all? If so, how low did you go and were you successful? We might have some options if we could get down to the +/- 1uA range.
I haven't modified the cheapstat to have a +/- 1uA range - however I'm pretty sure this should be doable.
Also, we have a new potentiostat design coming out soon which is basically a shield for the teensy 3.2 development boards (https://www.pjrc.com/teensy/teensy31.html). It has current ranges of +/- 1, 10, 100, 1000 uA and output voltage ranges of +/- 1, 2, 5, and 10V. We just got a batch of the new of the PCBs in - I've attached an image below. We should have them up on our website within the next 2-3 weeks.