Top-down of component on PCB

Top-down of removed component

Bottom of removed component

I believe it is either an inductor or a diode, but I'm not sure where else to begin. The voltage ratings are either 5VDC or 12VDC, and 28VDC was mistakenly applied to the PCB header. No smoke or anything was witnessed; however, when looking at the component with a thermal cam, this component heats up rapidly. Any ideas on what this component is?

Dimensions are 1.60mm long, 1.00mm wide, and 0.50mm tall

I did some research trying to find the specific package as well, but no such luck. Thank you all for your time.

  • 1
    \$\begingroup\$ Can you reverse engineer the schematic? If it's heating up quickly it's unlikely to be a damaged inductor; I would suspect a damaged diode. \$\endgroup\$
    – Hearth
    Oct 10, 2022 at 20:10
  • 2
    \$\begingroup\$ What does a multimeter read on it in diode mode and resistance mode? \$\endgroup\$
    – Bryan
    Oct 10, 2022 at 20:12
  • \$\begingroup\$ Diode mode shows continuity both ways, and resistance mode shows 50ish Ohms one way and 87 the other. I suspect it is a failed zener diode for a crowbar circuit, but I'm not sure where I would begin with determining specs for it. \$\endgroup\$
    – Grogglebob
    Oct 11, 2022 at 14:18

1 Answer 1


It's probably a diode marked "L" and the dot just indicates the polarity.

As for which diode, this list shows a few candidates: https://smd.yooneed.one/code4c00.html

Measure and determine the package, then use that to narrow down the possibilities. Then research datasheets to see if one is marked "L" (sometimes manufacturers list the marking code in the datasheet, sometimes not.)


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