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Projects => Power supplies => Topic started by: kunlun121 on December 28, 2022, 08:34:16 PM

Title: SSR01 malfunctioning
Post by: kunlun121 on December 28, 2022, 08:34:16 PM
Hi. I'd much appreciate some help on the 13V SSR01 I'm trying to build. I can't get it to work.

I am feeding it rectified / smoothed DC @ 21-22V, so well above the target output of 13V. The output of the SSR01 is not quite stable at around 18.2V. It looks like it's not going into regulation.

The build is using the LM431 as voltage ref. It has the AD825 that you soldered on the board. I used the 12V SSR01 version as I found it in the documentation. The only change to the BOM / schematic is adding 15K @ R17 to get 13V output.

Just now I have meticulously double checked each component against the schematic and the BOM. Everything is right where it should be.

I tried 13V (or 13.2V to be precise) in a different configuration: I removed R17 and changed R8 (1k) out for 1k2. Same thing: still not quite stable at around 18.5V.

What could I be missing? Are other changes to the schematic needed when adding R17 @ 15K?

Thanks for looking into this.
Title: Re: SSR01 malfunctioning
Post by: peranders on December 29, 2022, 07:12:46 AM
Tin drops on J1 and J2?
Title: Re: SSR01 malfunctioning
Post by: kunlun121 on December 29, 2022, 10:50:13 AM
They are there.
Title: Re: SSR01 malfunctioning
Post by: kunlun121 on December 29, 2022, 11:22:38 AM
I found something that looks odd. There were some more SSR01 boards lying around. It looks like the others have the AD825 rotated 180 degrees. It looks like this one is up side down. I e-mailed you a pic, dunno how to upload it into this thread. Does it look right to you?