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> Voltage Regulator
Guruji
Posted: July 02, 2017 11:50 am
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Hi I built this regulator but even lowering resistance pot I cannot lower voltage more than 8v out with 12v in. Why is this?
Any help please?

https://www.google.com.hk/search?q=lm317&pr...EeEfUn-h5QSVFM:
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Sch3mat1c
Posted: July 02, 2017 03:11 pm
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Does the pot resistance go to zero?

Do you have a minimum load on the LM317?

Tim


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Guruji
Posted: July 02, 2017 03:36 pm
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QUOTE (Sch3mat1c @ July 02, 2017 03:11 pm)
Does the pot resistance go to zero?

Do you have a minimum load on the LM317?

Tim


Thanks for response.
Ok I did a load but now going to 5.40v and staying there.
Changed the pot to 1k with same result.
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gremlinsa
Posted: July 02, 2017 05:48 pm
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Increase R2 (Double it to 480ohm) and you will shift the voltage adjustment scale down....


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dmg
Posted: July 02, 2017 06:51 pm
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needs a picture on how you connected the pot it self.
something tells me you got it wired up the wrong way.
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Guruji
Posted: July 04, 2017 12:08 pm
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QUOTE (gremlinsa @ July 02, 2017 05:48 pm)
Increase R2 (Double it to 480ohm) and you will shift the voltage adjustment scale down....

Thanks gremlinsa and Dmg I've put another pot instead 240ohm and adjust both until it came to 6v.
Ok worked.
Thanks guys.
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