I was just wondering if it is possible to use the LTC4121 as a solar charger for supercaps?
In my application I like to support both Li-Ion XOR supercap charging. (Little circuit modfications are ok)
The LTC4121 may be used to charge supercapacitors. Obviously, you'll want to set the maximum voltage to the manufacturer's recommended charge voltage using the resistive divider feedback from the supercapacitor. The LTC4121 is a CC/CV charger which means it will charge at the programmed constant current until the supercap voltage approaches the maximum value. At that point, charge current will be throttled back until the supercap voltage reaches the value established by the resistive divider. It should work.
That sounds good :-)
However I found something in the data-sheet under "Low Battery Voltage Operation" that makes me nervous:
Charging an 100F supercap with 9mA (linear charge) and 30 minute failure time-out is not satisfactory.
Is it possible to turn off the Low Battery Voltage Operation?
Is there an alternative LT or AD Devices around that can be used for solar charging (with MPPC/MPPT) Li-Ion or Super-caps efficiently?
Firstly, you get high marks for digging through the datasheet. Unfortunately, your analysis of the low-voltage-preconditioning feature (anti-feature, in this case) is correct. I am asking around to see what alternatives we may have.
Retrieving data ...