To achieve the most accurate current sense value, it is recommended 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 9-1 with typical values for the resistor and capacitor. The designer should
select a CSNS capacitor value based on system requirements. A larger
value will provide improved filtering but a smaller value will allow for faster
transient response.
- The ADC and microcontroller can also be used for filtering. It is recommended that the ADC collects several measurements of the SNS output. The median value of this data set should be considered as the most accurate result. By performing this median calculation, the microcontroller can filter out any noise or outlier data.