The LM320 is a negative voltage regulator up to 15 V with maximum current of 1 A. In this circuit we have its application as adjustable regulator up to 15 V. The integrated circuit must be equipped with heatsink. The formula to obtain the output voltage is next to the diagram. C1 and C2 are required if the input and the load are far from the regulator or have insufficient filtering. Typical value of R1 is 220 ohm.
