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MrBungle · 8th Sep 2019, 10:56 am

LM317 only goes unstable if the dropout voltage and the minimum load isn't respected. It'll quite happily run without caps in most cases believe it or not under load but best to put 1uF across output and 100n on input. It doesn't need any more than that if's DC in and out.

See my earlier post on the things wrong here. Main issue is not enough volts going in for the volts coming out.

8th Sep 2019, 10:56 am	#27
MrBungle Dekatron Join Date: Jun 2016 Location: London, UK. Posts: 3,687	Re: Defective/ fake LM317T LM317 only goes unstable if the dropout voltage and the minimum load isn't respected. It'll quite happily run without caps in most cases believe it or not under load but best to put 1uF across output and 100n on input. It doesn't need any more than that if's DC in and out. See my earlier post on the things wrong here. Main issue is not enough volts going in for the volts coming out.