For UPS Power Supply circuit consists of lowering the voltage, rectifier, charger, batery and regulators. The technique is applied from UPS on the power supply is the use of batery and charger is connected dengang direct coupling with a series diode. For more details can be seen with the following image.
The rectifier in the circuit UPS Power Supply For this to function also as a charger via D1. D3 function is to drain-source voltage of the rectifier to the regulator circuit, when the AC voltage source. D2 serves to drain the batery when the source voltage from AC voltage source does not exist. batery configuration and diode D1, D2 and D3 is adopted from the UPS system. may be useful and can provide inspiration on teman2 all in making backups on the system power supply voltage.