STM CircleOS forum / display & sound turn on and off intermittently

ccrisan · 2009-04-03 18:36:03

Lately my Primer2 began to behave strange. About less than a minute after turning on the device, the display and the sound stop working for 1-2 seconds. Then it resumes and continues to run the program, without reseting. This happens every few seconds as well, the "frequency" increasing (i think) with time. I don't know if it's an overheating issue, a software problem or something else. It happens no matter what CircleOS version I run on it (even without any application). Any idea?

repzak · 2009-04-04 02:22:35

Hello,

Sounds like the voltage regulator is getting to hot

Kasper

Francis · 2009-04-04 06:57:08

Several persons already encountered the problem (either with U9 or U17). In you case, U17 is 'altered', and "consumes" too much current (then the temperature level detector triggers periodically). I shipped one 'altered' device to ST for analysis, but they didn't find anything.
The problem generally occurs after touching the PCB with fingers.
You can ship your Primer to Raisonance and we will replace the regulator. It's also better to replace the input capacitors (U23-U56, tantalum) by ceramic capacitors. You can contact me by email for shipment details.

lucifer · 2009-08-01 11:42:15

@ccrisan: I've the same problem, did you solve the issue? Did you have to ship your device to Raisonance?

Thanks in advance!

Francis · 2009-08-03 07:08:51

I contact you by email to see how to solve the issue.

Yoshito · 2009-10-09 07:27:54

I have same problem on one of four units which I have.
I got some L6928Ds, and I can manage replacement by myself.
Is it better to you to ship the unit without fixing?

# I already added a ceramic capacitor to C23 and C56 on those units.

Francis · 2009-10-09 15:50:58

If you are able to replace the regulator, it would make things simpler (it's a pity to make an oversea shipment if we can avoid it). But if you cannot, ok.

Yoshito · 2009-10-13 02:55:34

I replaced U17.
It's working fine.

Thanks.

Francis · 2009-10-13 07:48:14

If such problems occur, replacing the input capacitors (C23/C56) by ceramic ones (instead of tantalum) is also recommended.

Yoshito · 2009-10-14 02:55:34

Thank you for your recommendation.
I already did it.
Not replacing but adding 10uF/10V ceramic capacitors as below.

+----------+
| tantalum |
+----------+
| ceramic |
-------------------------------------
PRINTED BORAD
-------------------------------------

Francis · 2009-10-14 06:56:55

Yes, combining advantages of both is better.... Thanks.

# 1 2009-04-03 18:36:03 display & sound turn on and off intermittently

display & sound turn on and off intermittently

# 2 2009-04-04 02:22:35 display & sound turn on and off intermittently

Re: display & sound turn on and off intermittently

# 3 2009-04-04 06:57:08 display & sound turn on and off intermittently

Re: display & sound turn on and off intermittently

# 4 2009-08-01 11:42:15 display & sound turn on and off intermittently

Re: display & sound turn on and off intermittently

# 5 2009-08-03 07:08:51 display & sound turn on and off intermittently

Re: display & sound turn on and off intermittently

# 6 2009-10-09 07:27:54 display & sound turn on and off intermittently

Re: display & sound turn on and off intermittently

# 7 2009-10-09 15:50:58 display & sound turn on and off intermittently

Re: display & sound turn on and off intermittently

# 8 2009-10-13 02:55:34 display & sound turn on and off intermittently

Re: display & sound turn on and off intermittently

# 9 2009-10-13 07:48:14 display & sound turn on and off intermittently

Re: display & sound turn on and off intermittently

# 10 2009-10-14 02:55:34 display & sound turn on and off intermittently

Re: display & sound turn on and off intermittently

# 11 2009-10-14 06:56:55 display & sound turn on and off intermittently

Re: display & sound turn on and off intermittently

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