Which among the circuit is the most efficient one for a battery backed up solution. Would be helpful if you can state the reasons as well.
- Power Supply - 15V, 1.4Amps (SMPS)
- Battery - 12V, 11.2Ah (SLA)
- Load - 3.3V, 250mA
- Charger - Float Charging (13.6V Max)
- Voltage Regulator - DC to DC buck (4.5 ~ 50V input)
- Some components are not shown since they are not relevant