Could you give me some hint?
I have connected a CT sensor (current outuput) to an Arduino ATmega 2560 and I have got some realistic values.
I used the schematic from here: http://openenergymonitor.org/emon/buildingblocks/ct-sensors-interface
The burden resistor I used was a 120ohm one (based on the calculations) in order to get the voltate in Arduino's range.
Now I would like to move the project to an Attiny85. The first thing I used was to put the code with no modification, and the values I got were quite different.
After a bit of research I instructed Attiny85 to use the internal refference voltage of 1.1v and re-calculated the burden resistor to ~30ohms.
Now the problem is that analogRead() on the pin connected to the current senzor gives me constant 1023, even if there is nothing connected to the plug.
What do I do wrong? Is the burden resistor correct?