Hi everyone,
I'd like to present you my supercapacitor load balancing circuit. There are many of those but they usually consist of a pair of transistors that are partially open during overvoltage of a supercap and thus constantly generating heat due to power dissipation. When transistor is partially open it has a high Rds(on) and this is how most of a cheap supercap load-balancer circuits are made. Yes, it's quite ok from a view of price but I personally do not like that approach and that's why I have created this circuit. It is more expensive but allows the whole circuit to stay at a reasonably low temperatures as it turns MOSFETs on for a short period of time (dependent on input current) and fully opens MOSFETs so they produce a very low resistance and most of the heat dissipation occurs in Rs resistors which you can have as many as you like to suit your input power. Furthermore, this circuit allows a use of any kind of supercaps up to any voltage and number of them, you just need to replicate the schematic when adding more supercaps.
You can have a look at the project and all the documents including Gerber files, schematics and PCB here:
https://workspace.circuitmaker.com/Projects/Details/LtFlash/Supercap-BalancerThanks and please do not hesitate to ask any questions!