FEZ Panda gets very hot!

I just recieved my FEZ Panda, but when I plug it into USB, the IC3 get’s vey hot (>100 °C) within seconds. Is this normal, how can I fix it? Should I send it back?

The board works normal otherwise…i.e. I can ping it and check the firmware version. I only tested it for a few seconds, because it really, really gets hot.

Thank you!

If only USB is connected and nothing else, that sounds like a problem to me

No, nothing elese is connected.

Please contact GHI directly for further steps. Boards are tested ab packaged right before they ship but we will work something out to make sure you are happy.

Same problem here.

My FEZ Panda I just received loads and runs code (for now) but becomes extremely hot during use. I think the heat is coming from one of the smd voltage regulators. I have not left it plugged in via usb for very long because I start to smell burning plastic after a while.

It cant be very safe for the device or me because any touching during operation causes burns to my hand

Maybe there was a bad batch?

Ill be contacting GHI support then I guess.

Is it hot if you use the power connector?

Just hooked up 4 AA batteries via the barrel jack and am not getting the same problem. Gets warm but nothing unusual among regulators that I have worked with

Looking at the traces its not obvious where the power problem is

just compared my board with the schematic to try and figure out what the problem is

One difference between my board and the schematic is that there is no R2 present (the resistor associated with IC3, the IC that is generating all of the heat

Is the fact R2 is missing a manufacturing defect or was it intentionally left out

My Panda doesn’t have R2 neither and no problems here

No R2 shouldn’t be populated, this is normal.

Please see this new post http://www.tinyclr.com/forum/2/1703/

Did everything in that post.

Is it just me and the other guy in this thread having the problem, or have others reported it?

That is why we want you to send emails so we can see who has the problem and why …etc.

so…would it be possible to swap boards out? Or what is the ultimate solution to this problem?

I really want to start developing on my board. I am planning on using it for my group senior design project for next semester and I want to start getting familiar with it.

I am hesitant because I do not want to fry it (or my USB controller for that matter)

You will not fry it. The regulator has thermal protection

Please send an email directly to GHI like the other post said and the guys will take care of you

Do not worry, you are in good hands :slight_smile:

I think the following is the problem:
When the input pin of the 5V regulator is lower than the 5V, the IC3 is not working and some of the internal transistors are floating/leaking the current from the output to common ground. This heats the device. The thermal shutdown is not active in this mode, because -as I said- the device is not working in normal mode. If my USB port would supply more current, I’m sure it could desolder itself from the board.
When you connect a 12V power-supply, the input pin of the 5V regulator is high enough and the device works normally.
The only fix is to change the IC3 with a device that tollerates these operating conditions.

Ok, there is something weird going on with that voltage regulator. An hour ago, the behaviour of my FEZ Panda changed. Now the IC3 gets hot when I plug use the 12V plug, but stays cold when I power it from USB. I don’t know what caused that change.

There is a post about this already with instructions. Look at posts in this board

Chris_, your problem is not related to post Gus mentioned.
What do you have connected to your FEZ Panda? If you have likeEthernet shiled or display connected to, then you need to use 6 or 7.5 Volts to power it.

The reason is, the more the power consumpltion the more heat the regulator should dissipate.

Try it with 6.0Volts only

Just got my replacement FEZ Panda in the mail. Works great so far (hooray!), and there is no sign of the previous problem

I will be shipping the defective one back tomorrow.

No, I only have the bare Panda board connected. The only cable connected is a stabilized 12 V power source. It overheats in seconds.
I’ll request a replacement.