Measuring current and voltage using 3DR power module and arduino
I used to use Allegro ASC current sensor like this one. since it's calibration free, and out put voltage according to voltage. But these sensors are not easy to get in taiwan, and quite expensive. As APM is popular, the 3dr power module comes with different source, good price, with 5V supply on it. this one should be handly. while saying it's open source, I'm not quite sure where to get the code today. But a good source from sparkfun comes out form googling. it's a attopilot voltage and acurrent sensor breakout, there are 90A and 180A versions. https://www.sparkfun.com/products/9028 Both are constructed with a shun resistor and a TI INA-169, which will out put a current based on the voltage difference on both side of shun resistor. Crossing this current through a resistor which connect to ground, then we have a voltage on this resistor, which is in function with the current. As to voltage, there is a set of dividing voltage. The good t