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PIC Balancer - Preventing Voltage Overshoots

This illustrates how the balancer terminates a discharge cycle when voltages overshoot the lowest:
There is only one cell high here (blue diamond) so it is getting 100% duty cycle
With a 100% duty cycle, the cell can be discharged for 100 iterations of ~40ms in each cycle (~4s total)
Voltages are measured every 40ms to prevent over-discharge so after about 10x40ms the cycle is stopped
The 40ms is actually a 20ms delay plus about another 20ms of processing time with all the calculations
The cell is allowed to rest for 4sec when this happens so it's voltage recovers almost completely
In the next cycle it only completes 7x40ms before falling below the lowest, then 6x40ms etc
The graph also illustrates the small voltage fluctuations in lowest cells due to switching & other noise

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