STM CircleOS forum / another damaged primer

lpdunwell · 2010-01-07 17:05:13

Hello
I just got my primer 2 today, it worked for a short time, then some nasty things happened:

- the maze example sometimes ran at higher speed (twice as fast, the difference is easily audible)
- first i realized the thing gets really hot
- after a visual check i burnt my finger on u17, finding a solder "jumper" over pins 1 and 2
- removing the solder jumper didn't improve things. u17 still was incredibly hot.
- looking at u9 (same ic, chance for same problems? i thought) i found some solder droplets.

Working for a rather big electronics company in which i have contacts to the smd plant, i know how and why these things happen. As a matter of fact I'd like to have this replaced so if anybody could tell me the best way, that would be great. I have ordered it from mouser.com.

Thanks
best regards, Luke

yrt · 2010-01-08 07:43:50

Hi Luke,

Refer to the topic "U9 & U17 Voltage Regulator Failure" of the "Resources/How to/Resolve/Known problems" page.

FYI, we repaired several Primer2s that had either U9 or U17 dead. When we repair them, we replace the dead regulators, but we also replace the U23/U56 capacitors (input voltage for the regulators) by multi layer ceramic capacitors (instead of tantalum). It seems that it solves the problem.

Yves

lpdunwell · 2010-01-08 10:35:52

gerber files and pdfs found on this page differ from the primer 2 i have here in my hands:
if i look at u9, u10 is to the left of it, c23 and the protection diode as a hand modification are above u9...

lpdunwell · 2010-01-08 16:40:34

any ideas?

lpdunwell · 2010-01-10 00:20:44

I have a Primer 2 V1.2. Documents are not this revision.
(http://www.stm32circle.com/forum/viewtopic.php?id=949)

EDIT: I have no idea, if the Supply problem still exists, or if the soldering faults simply burnt u9 and u17. So now I'm basically waiting for recent documentation.

Last edited by lpdunwell (2010-01-10 00:22:20)

yrt · 2010-01-12 07:57:11

Hi,

FYI, the PCB is v1.2 version and the available schematics version is v1.1.

For you problem, the best way is to exchange your Primer.
We will contact you by email.

Yves

lpdunwell · 2010-01-12 10:21:45

I will send it off tomorrow
thanks a bunch

# 1 2010-01-07 17:05:13 another damaged primer

another damaged primer

# 2 2010-01-08 07:43:50 another damaged primer

Re: another damaged primer

# 3 2010-01-08 10:35:52 another damaged primer

Re: another damaged primer

# 4 2010-01-08 16:40:34 another damaged primer

Re: another damaged primer

# 5 2010-01-10 00:20:44 another damaged primer

Re: another damaged primer

# 6 2010-01-12 07:57:11 another damaged primer

Re: another damaged primer

# 7 2010-01-12 10:21:45 another damaged primer

Re: another damaged primer

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