1

Im building a LM317 based power supply and the output range must be 0.3V-21V. I've used a 2 diodes in series and a resistor supplied by a negative voltage and take the node between resistor and diode to be a negative reference to be fed to the adjust pin of LM317 to reduce its reference voltage. Now, I found other people saying TL431 is much better reference voltage but I dont know how to reduce its reference voltage. Can someone help me?

rlmarco
  • 35
  • 1
  • 3

1 Answers1

3

Now, I found other people saying TL431 is much better reference voltage but I dont know how to reduce its reference voltage

You can't reduce the reference voltage - it is fixed at 2.5 volts but you can certainly use it as a

negative voltage reference

enter image description here

Andy aka
  • 456,226
  • 28
  • 367
  • 807