Can I (attempt to) measure a voltage that is higher that the ADCs Vref, without damaging my IC?
I'm trying to measure the battery voltage using a resistive divider, and using the internal 1.1V bandgap voltage. I selected the resistors so the voltage would be around 1V when fully charged.
My project can however also be power by a wall-adapter, which exceeds the batteries voltage, resulting in a voltage higher than 1.1V at the ADC.
In the datasheet the table of ADC Characteristics seems to indicate that the maximum input voltage is Vref. Though I'm not sure if that's the maximum voltage is can convert, or if that's the maximum voltage that's allowed.
Elsewhere in the datasheet it says:
Single ended channels that exceed VREF will result in codes close to 0x3FF, which seems to indicate it isn't a problem to exceed Vref (as long as it's below Vcc).
The part I'm using is an ATtiny13A, but the relevant sections of the datasheet seem identical to the ATMega328.