L9966 Resistance measurement overall accuracy

[DavidL]

hello,

L9966 datasheet (§8.2) mentions a max total resistance measurement accuracy of 1.5% (if CALIB_SEL=1).

It seems that such accuracy does not include external pull up RRx accuracy which should impact the overall measurement accuracy and therefore going above 1.5%, if I am not wrong.

I am seeing that "no ratiometric comparator is running" (talking about VDD5REF I suppose).

Please, how could I foresee the impact of RR1/RR2/RR3 accuracy on overall measurement accuracy?

How could I get rid off the VDD5REF variations, maybe by enabling this ratiometric comparator, how to enable it?

Thanks beforehand. 

[armitage.richard]

I am going to use 0.1% resistors like evaluation board, and sense VDD5REF. I wonder if the switch resistance can be measured and removed?