The LTC3643 is a single-inductor, 2A bidirectional charger and backup supply similar to the LTC3110 SuperCap device, but is meant for an electrolytic capacitor array. The LTC4040 is the closest equivalent charger and backup supply, but is meant for Lithium batteries. An alternative Linear Tech solution may be constructed from a high voltage buck such as LT8609, a high voltage boost such as LT1618, two inductors, and a comparator. The primary differences between the LTC3643 and the LTC3110 are: the LTC3110 has lower voltage operation and is tailored for SuperCaps, LTC3110 has lower quiescent current of 40µA, there is an auto-cell balancer present on the LTC3110 which is not needed on the LTC3643, the LTC3110 has V_IN current monitoring, and the LTC3643 has a smaller QFN footprint/package of 3mm x 5mm Vs. 4mm x 4mm.