Current counting analog-to-digital converter for load current sensing including dynamically biased comparator

摘要

In one embodiment, a circuit comprises first and second capacitors configured to receive a sense current in first and second modes, respectively. A comparator is coupled to the first capacitor to compare a voltage of the first capacitor to a reference voltage and generate a count signal in response to the voltage of the first capacitor reaching the reference voltage in the first mode. The comparator is coupled to the second capacitor to compare a voltage of the second capacitor to the reference voltage and generate the count signal in response to the voltage of the second capacitor reaching the reference voltage in the second mode. A reset circuit discharges the first capacitor in the second mode and the second capacitor in the first mode in response to the count signal. A counter increments a count of a number of occurrences of the count signal.