I'm using an external reference voltage connected to the VREFH pin of the kinetis microcontroller. The total supply current should be very low, so I want to be able to shutdown the external reference when I don't need it and continu to use an internal reference. The problem is that the minimum voltage on the VREFH pin is specified as 1.13V and the voltage will drop below this when the external reference is disabled. So the question is, do I need to make sure that the voltage on VREFH is always above 1,13V or may it drop below this when using an internal reference and does this requirement change when not using the ADC at all?
With kind regards,