To achieve the most accurate current sense value, TI recommends to filter the SNS output. There are two methods of filtering:
- Low-Pass RC filter between the SNS pin and the ADC input. This filter is illustrated in Figure 10-1 with typical values for the resistor and capacitor. The designer must select a CSNS capacitor value based on system requirements. A larger value provides improved filtering but a smaller value allows for faster transient response.
- The ADC and microcontroller can also be used for filtering. TI recommends that the ADC collects several measurements of the SNS output. The median value of this data set must be considered as the most accurate result. By performing this median calculation, the microcontroller can filter out any noise or outlier data.