I'm building embedded system based on a Raspberry Pi with an MCP3008 for analog inputs. I have few questions regarding the PCB board design.
- What should I do with unused analog inputs on my MCP3008?
- What other countermeasures I can use for minimizing the analog noise jeopardizing my ADC measurements? I don't want to use analog ground because that requires another supply circuit for ADC board and I want to power up the MCP3008 directly from my Raspberry Pi.
- Any other advice?
For now I'm working with a prototype on a breadboard. The wires are long and unused ADC inputs are not connected to a ground. I can see quite a large amount of noise from time to time on my analog readings and I want to come up with good enough countermeasures in my final project in order to minimize noise observed on my prototype.
Final Project Results: http://maqister.blogspot.com/2016/08/my-homemade-raspberry-pi-expansions.html