I've seen in section 7.1 of the datasheet that an external voltage can be used to set the MPP point. I suppose you have to introduce the external voltage directly in the VREF_SAMP pin. In this case, can the periodic sampling be disabled? I've seen that this is possible with the BQ25504 IC by tying the VOC_SAMP pin to VSTOR but if you do this for the BQ25570 IC, it is specified that the MPP voltage will be 80 % of the input open circuit voltage. And a I've found no indication of how disabling the sampling process, if possible.