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LM317 Adjustable Regulator Voltage?

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New Member
See attachment for schematic.

I've built the circuit in question according to the LM317 datasheet schematic. I'm supplying 15VDC. As per the equation, the output voltage should be:

1.25(1 + R2/R1)

When R2 = MAX = 1k and R1 = 110, I should get around 12V out...I am, however, only getting around 9V out. I don't see any restrictions for this and I have not loaded the circuit...I'm stumped on this one. Any ideas?



Well-Known Member
Most Helpful Member
Your 10uF capacitor in in the wrong place. It makes the LM317 oscillate.

Your input capacitor also is in the wrong place.
Why not copy the correct circuit in the datasheet?
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