How to judge the sampling signal for MM9Z1J638BM2EP

[chris_zhang]

Hi All,

     We used the MM9Z1J638BM2EP to the current sampling for the BMS project, the ISENSEH and ISENSEL connect to the shunt resistance, now, there is risk for this circuit because MM9Z1J638BM2EP can't judge the sampling signal is the shunt resistance voltage divider or floating voltage, and there are no FB pin in the MM9Z1J638BM2EP. So please advise how to solve the problem? thanks.

[guoweisun]

Hi

You can't get rid of this shunt sense offset parameters even if in actual application,so suggest you select the shunt resistor(200 μΩ) as large as possible to decrease this offset affect.

[chris_zhang]

Hi G.W,

Thanks for your kindly comment.

And I mean we can't identify the signal is the sampling of shunt resistance or NC pin signal(Circuit short circuit), thanks 

[guoweisun]

Yes,actually lower than 5mA current is hard to detective accurately which includingyour mentioned short condition.