App note: Troubleshooting switching power supplies

Posted on Sunday, February 2nd, 2014 in app notes by DP


Having problem with your switching power supply design? Or just curious on common switching power supply failures. Here’s a good resource from Micrel on troubleshooting power supplies.

This application note provides insight on troubleshooting and
taking measurements in switching power supplies. Specific
measurements include output ripple, line and load regulation,
efficiency, and transient response. Troubleshooting and
measurement of flyback and forward converter transformers
are also covered.
Common measurement mistakes are also demonstrated,
including using uncompensated scope probes. The final topic
is an in-depth example of troubleshooting an off-line flyback
power supply. Off-line flyback topologies involve all dc-dc
converter circuit blocks, plus the ac front end, thus cover most
troubleshooting problems.
This entry was posted on Sunday, February 2nd, 2014 at 1:00 pm and is filed under app notes. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.

2 Responses to “App note: Troubleshooting switching power supplies”

  1. shiraz says:


  2. Peter says:

    A very timely link. I had a computer power supply on an old computer go out a few weeks ago. It wasn’t worth it to buy a replacement given the age of the computer- a P4 that I use as a CNC interpreter (linuxcnc). It is getting harder and harder to find computers with a parallel port however. I tried looking online for resources to help diagnose switching power supplies with limited success. This looks like a very good resource. I am going to open up the power supply and give it a shot.

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