Conclusion

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Conclusion

When a current sensing works in a high frequency noisy environment, it is mandatory to

correctly filter the input of the TSC device, avoiding any parasitic offset due to the high

frequency spikes. Both common mode and differential mode paths must be filtered. The

best scenario is to match the capacitance between them to avoid adding differential error

on the input of the current sensing.

Otherwise, it is important to combine a common mode filter and a differential mode filter to

compensate the mismatch of the capacitance (see Figure 18: "Configuration to filter a high

frequency signal").

It is also important to match the resistances to avoid error on gain and consequently, an

error on the precision of the current measurement.

Figure 18: Configuration to filter a high frequency signal