In article , pmg3 @op.plNOSPAM says... | How should I change the resistors R1, R2 and R3 in |
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| if I want to obtain a 5V-30V voltage range instead of 24V-70V??? |
The potential divider R2/R3 sets the voltage of feedback to pin 3, with some offset available via 'Control Input' of R1.
For experimental purposes the best way to do it would be to replace R2
- R3 with a potentiometer of 200 to 300k Ohms, attaching the middle sliding contact of the pot to pin 3.
The more the potentiometer slider is adjusted towards ground, the higher the voltage output will be. The more it is adjusted towards the positive output, the lower the output voltage will be.
Once you have found a setting for the experimental potentiometer with which you are happy, measure the values either side of the sliding pin and fit fixed values of resistance in its place.