I'm using the Arduino Mega to read inputs from multiple sensors. Currently I have a total of 35.45 mA being pulled out of the 5V supply pin. I'm wondering if I need to add up to two more sensors what the max Amps that are able to be pulled from that 5V supply pin? Is it 40mA total? If it cannot should I run the extra sensors through the digital output pins?
Also can the Arduino handle an additional 4-20mA pull into one of the analog input pins?
You should not be using the IO pins to connect direct to a 4-20ma sensor. Use the current from the sensor to develop the voltage across a resistor and measure the voltage.
What sensors are you using and powering from 5v? Most 4-20ma sensors would need more than 5v. More like 24v.
A circuit of how you are connecting things would clarify the situation.
Weedpharma
Currently I have a total of 35.45 mA being pulled out of the 5V supply pin.
Answered this in the last few days. Is it a class assignment?
From the 5V pin you can pull 500mA when powering from the USB and slightly more when powering from an external supply. How much more depends on the input voltage.