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ACS724 Filter Cap

The ACS724 breakout has pins for a filter Cap. You state further information is in the datashet. I’ve looked through and searched the Allegro data sheet for information on Cf, a nominal value of 1nF is given but I cant find anything on how this value effects bandwidth or filtering of the the output. Can you point me in the correct direction. :slight_smile: Thanks, John

Hello, John.

The important detail from the ACS724 current sensor’s datasheet is that the external capacitor added to the filter pin forms an RC circuit. As given in the common electrical characteristics table (on page 5), the internal filter resistance (i.e. the R value for the RC circuit) is 1.8kΩ. If you do not know much about how RC filters affect signals, this “RC Circuit” Wikipedia article might be a good place to start.

- Patrick

Thanks Patrick, that helps a lot. John.

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