How to protect analog output (current protection) ?

Using Arduino General Electronics
12

dammien:
Hi all,

Thanks to my Arduinos I can generate some real analog values. It can be made through the onboard DAC of the DUE, or with an external DAC like MCP4912.

I am looking for a component to put after the DAC, that does the following job :

  • under a certain amount of current (for ex 10mA), the output voltage is exactly the DAC output
  • when there is an overload, more than 10mA, the output voltage can deviate from the DAC output to limit current to 10mA
  • as soon as load is back to normal, output voltage is back equal to the DAC output
    To sum up, from the DAC point of view, there is no overload. this one always outputs its voltage in safe circumstances.

So, what is the best and easy way to do this ? are there integrated circuit for this ? Should I use an operationnal amplifier ?

THanks for your answers.

Google "foldback current limiting". That sounds like what you are looking for.