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I'm trying to use a switching regulator (ptr08060w) to step 12V DC down to 2V DC, however it is not achieving this at all (even with no load connected), and is outputting a voltage that varies randomly between 0.6 V -> 1.6 V, sometimes oscillating, sometimes steady at one of the incorrect voltages, sometime is starts to work (outputting a stead 2V), but then stops again after a random time. The voltages at the other pins of the regulator are constant, regardless of whether it is behaving or not.

This is related to my other question, in which the regulator's output was changing only under load, I realized I had wired the op-amp incorrectly, causing the MOSFET to open too much, causing to much current; I fixed this and it worked fine from there until this issue arose.

It's not overheating (at least, it doesn't feel hot at all on my finger), does anyone have any ideas what else could be causing this?

enter image description here

UPDATE: Ok it seems to be working now (I did nothing) but my question still stands

UPDATE 2: nvm it's not working again - perhaps it's a connection problem? this is my first time using a vero board so all my solders are pretty bad :(

Pics of circuit (ik it's bad it was my first time):

enter image description here enter image description here

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    \$\begingroup\$ Put a schematic. Layout and a photo of the whole setup help as well. \$\endgroup\$
    – Rohat Kılıç
    Commented Aug 8 at 13:49
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    \$\begingroup\$ Dip - Hi, This is a slightly different problem description to your question from yesterday, as you are now saying the output voltage fluctuation occurs even without a load (yesterday, you said it only occurred with a load). However, when you're posting questions that are clearly related, it's important that you include details that are missing from here: Mention & link to relevant previous questions, and explain why later questions are not duplicates. Explain what is different, what you have changed etc. So while each question should be "standalone", don't hide the context. TY \$\endgroup\$
    – SamGibson ♦
    Commented Aug 8 at 13:56
  • \$\begingroup\$ @RohatKılıç , Done \$\endgroup\$
    – Dip
    Commented Aug 8 at 14:22
  • \$\begingroup\$ 1) What are the PN#s of the capacitors you used? 2) Have you tried to apply a steady-state load (aka no PWM)? \$\endgroup\$
    – RogerDodger
    Commented Aug 8 at 15:03
  • \$\begingroup\$ @Dip - Thanks for adding more info. However the "it's working", "now it's not working" updates suggest there could be a more fundamental issue, which is difficult to diagnose remotely e.g. the soldering concerns which you mentioned. I suggest you consider adding photos of the actual hardware with close-ups of the soldering, as that might allow people here to spot problems. But it can be very difficult to identify some poor solder joints remotely, \$\endgroup\$
    – SamGibson ♦
    Commented Aug 8 at 15:08

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