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GrandCentral Shorted Pins
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GrandCentral Shorted Pins

by sandoralex on Tue Feb 12, 2019 7:34 pm

Hi,
I orderd two Grandcentral M4 Express boards, and one appears to have a solder bridge across two of the pins. The order # is 1969928-5297158272.
I have uploaded a picture showing the problem. The board on the right has the pins near the silkscreen in the area of the letter 'e' in Atmel.
I have not powered on the board as I am not comfortable doing so with the pins shorted.

Grandcentral2.PNG
Photo showing the shorted pins.
Grandcentral2.PNG (473.83 KiB) Viewed 99 times


Please advise.

Thank you, Alex

sandoralex
 
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Re: GrandCentral Shorted Pins

by adafruit_support_bill on Wed Feb 13, 2019 6:57 am

Looks like pins 108 and 109 on the TQFP. pin 108 is connected to the on-board Neopixel. Pin 109 is unused. Go ahead and power it up & verify that the neopixel is working.

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Re: GrandCentral Shorted Pins

by sandoralex on Wed Feb 13, 2019 1:30 pm

Hi Bill,

I uploaded the neopixel test sketch, and the neopixel seems to be operating fine, so I will accept the board as is.
Hopefully there are no other issues with soldering on the board. Time will tell.

Upon closer examination of the board using my USB microscope, I noticed that the Atmel chip has solder flux left on the pins. Should I clean it off?

Thank you,

Alex

sandoralex
 
Posts: 5
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Re: GrandCentral Shorted Pins

by adafruit_support_bill on Wed Feb 13, 2019 1:58 pm

That is what I would expect. We do test every board as they come off the reflow line, so most harmful soldering issues would be detected at that time.

We use a "no clean" flux which does leave a small amount of harmless residue. You can clean it if desired, but it is not necessary.

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Re: GrandCentral Shorted Pins

by sandoralex on Wed Feb 13, 2019 2:18 pm

Thank you for your help Bill!

Alex

sandoralex
 
Posts: 5
Joined: Wed Feb 01, 2017 7:18 pm

Please be positive and constructive with your questions and comments.