Q. Ref LM338T in the TO220 package, I wish to construct the adjustable voltage regulator in the schematic on page six of the PDF's. It will need to give an output of 5volts and the existing circuit I have draws 650ma. My question is what should the variable resistor (R2) be rated at in terms of watts please? Also if you could make a possible recommendation of a suitable component together with part number from your range that would be most helpful. For info I have tried using the more common 7805 chip to power this circuit, which is supposedly rated at 1.5amps max, however I find it gets rather warm even with an aluminium heat sink, hence opting for the rather higher output of the 338. Best regards Mike B.
A. Hi Mike, thank you for your question. Standard 0.25W resistors are used for the voltage setting circuit.
