Example circuit with an F12C20C dual rectifier?
You can use this as a full-wave rectifier if you have a centre-tapped tranformer:







simulate this circuit &ndash; Schematic created using CircuitLab

The maximum current depends on how good a heat sink you have, but several A are not a problem with a small heatsink, and the maximum AC voltage would be more than 50V (the PIV rating is 200V, so if everything was perfect 140VAC would be okay. The output will be `1.414 times the input voltage AC minus a bit for the diodes, so a 12:12 centre-tapped tranformer (24V from end to end) would give you about 16VDC, give or take depending on capacitor and load.