Patent attributes
A simple digital-to-analog converter (DAC) may be used to monitor a load current. The DAC may be configured to generate a voltage corresponding to an estimate of an average value of the load current. A comparator may be used to compare that voltage with a sense voltage corresponding to the actual load current. The estimate may then be adjusted based on a sample of the comparator output, allowing the estimate to track the load current over time, thus providing an average measurement capability without using a fast analog-to-digital converter. The DAC may additionally be configured to generate respective voltages corresponding to specified over-current (OC) and under-current (UC) values. The comparator may then be used to compare these respective voltages with the sense voltage to respectively detect OC and UC faults. Noise immunity may be increased by integrating a number of comparator samples instead of a single comparator sample before adjusting the estimate. Increased noise immunity may also provide a measure of the error between the estimate and the actual load current, improving the efficiency of monitoring the load current.
