I'm working on a microcontroller-based device, and I need it to detect an input voltage (distinguish between zero and non-zero). When it's not zero, it can be anything between 10 V DC and 14.6V with some added noise of various frequencies. When it is zero, it will either be at GND or floating, I'm not sure yet.
Can I use a 5V Zener diode to stabilize this voltage and connect to the 5V-tolerant MCU's input? The current consumed will be however much the MCU requires, I expect it to be in the range of 1-3 mA (but I should probably see if I can find input current in the MCU's datasheet, which I couldn't so far but I'm sure it's there).