I have recently purchased 10, 3W LED Prolight Stars (90L High Power LEDs) with a Forward Voltage of 3.3V~3.5V and a forward Current of 700mA, I have a lot of PP3 9 volt batteries and wish to use them up in a new home made bedside light, obviously if I connect directly to the battery they will burn out, I have been looking for a voltage regulator circuit and I think the LM317 or LM338 voltage regulators would fit the bill, would anyone be able to tell me if this is a good idea or is there a better way of getting 3.3volts out of a 9volt battery while maintaining battery life?