Lastly, it is important to note the

Lastly, it is important to note the range of open circuit voltages and short circuit currents that this designcan operate under. To give the algorithm adequate headroom to search for the MPP, the minimum VOC isgiven as 4.5 V. Because this implementation of the algorithm operates between 65% and 95% of thisvalue, and the bq25895's lowest operating voltage (for charging mode) is 3.9 V, the code clamps the lowerbound of the Tracking loop to a 3.9 V VINDPM value. Note that this value must be increased depending onapplication in order to meet the Power up REGN Regulation (LDO) section's requirement of the charger[1].Figure 10 and Figure 11 show the MPPT performance with a low VOC at 4.5 V. Two points of note here arethe clamping voltage at start of the Tracking phase, and the short tracking time due to Preconditioningrange limits.