I've just had a thought - I'm currently protecting a design I'm working on from overcurrent by using polyfuses, so any component failures that lead to shorts to ground, or any external sensor and/or wiring faults that cause a short to ground will cause the polyfuse to trip and the power to be cut.
However, if I were to introduce a FET into the power supply (infact, I've already got a p-channel FET providing reverse polarity protection), and directly measure the current drawn then I could have the controller switch off the FET if a current threshold is exceeded for a certain amount of time.
How does one go about measuring current drawn by a device, and in such a way I can convert this to an analog voltage and feed it in to an ADC pin? I'd imagine I'd filter the signal first as there are plenty of current spikes in my application?
It seems a shunt resistor is my only real option?