Limenet Micro v2 over powered 12v

[blupastu408w]

I purchased this board on Amazon where the seller said it would accept 12v on the barrel jack. Obviously this is not the case. I guess the limenet micro v1 can run on 12v but 12v on the v2 lets the magic smoke out. It still powers up (some led’s light up) but does not function.

I’ve noticed the chip in the ic39 position gets really hot very quickly when the 5v power supply is connected, either via the barrel jack or ext pins. Im assuming its leaking most incoming power to GND. Is it possible to cut/bypass the barrel jack power regulation and power it a different way? Or would anyone have any suggestions as to which component or components could be replaced to rectify the situation? I highly doubt a RMA request would be accepted since its been purchased via amazon and is beyond the time constraints…

[andrewback]

I’m afraid it also wouldn’t be eligible for RMA if it’s had the wrong voltage applied.

@Zack, any suggestions as to where they should focus efforts repairing?

[blupastu408w]

that’s kind of what I figured also. I’m sure people lie about these things but I’d rather support the project and just buy another if I can’t get this one going.

This looks like an obvious hot spot. Going to hunt down the schematics and go from there. Thanks for the reply Andrew

[blupastu408w]

if I’m able to get it working i’ll be sure to post back. I’m sure I’m not the only one who’s had this happen, might be helpful for someone else at some point.

[blupastu408w]

coil/flyback transformer and diode look damaged

[blupastu408w]

Interesting… the crowd source site says “barrel jack for 12v power”. I see now why the amazon seller was confused. and now i’m confused.

LimeNET Micro

[mzs]

Pulling up the schematic (see page 15 for the actual details):

The original hardware revision from 3 years ago (2v0), expected at least 12 V DC (reusing part of the circuitry for Power over Ethernet):

But the current hardware revision from 2 years ago (2v1) is 5 V DC.

[blupastu408w]

thank you MZS that’s helpful. there’s definitely some confusion over power requirements/tolerances in more places than one. I"ve not gotten around to fooling with the Limenet but hope to have some time in the coming month. If I’m able to get it going I’ll report back what I did.