Thanks, so i keep the TL431 circuitry to limit the voltage to the floating voltage, and the UC3844 will handle current limit.. so nothing to change on this power supply , it will work as it is, i just have to fix the voltage limit to 13.8 and the current limit with the current limit resistor in the UC3844 and that's it ...
Bring an other question ... it's just to damn simple why a dedicated charging chip like the LTC4000 or UC3909 both cost 6 to 10 euro are needed for