lidas

I am looking for someone capable of progettarmi a circuit that led to a 28 / 30v feed me from a 12-volt power to the LEDs to function also needs 1.5 / 3 Ah I have to feed this led http://www.digikey.it/product-detail/it/bridgelux/BXRC-40A4001-F-03/976-1235-ND/5048136 I wish the circuit has the ability to vary the volts in output and also the amps and that can dim the LED 100% 60% 30% can you help me