Published by Andrew Zonenberg

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VCCINT measures 1.3 ohms to ground. That sounds... not healthy.

Betting it's a solder defect, the paste print there was not very good.

Time to hot air off the DC-DC and see if it clears the short, I guess?

I don't think it's the FPGA, it tested good earlier in the day and I baked it for quite a while before reflow just to make sure.


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Andrew Zonenberg

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VCCINT_EN is 18 ohms to ground, while GTY_VTT_EN is much higher (many K ohms). Both use the same DC-DC module.

So I consider that proof of a short under the Murata module for VCCINT.

This explains why the output wasn't even moving on the scope, the module was never turning on.


Looking more I see *five* mid chip solder balls on this module. I don't think it's happy at all.

by Andrew Zonenberg ;


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