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Altera_Forum
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8 years ago

Stratix5 - VCCCORE to GND resistance is almost 0 ohm

Hi, We have designed a PCB for the Stratix V device. We found the resistance between VCCCORE and GND is almost 0 ohm, thus we never powered it up. To clarify the problem, FPGA was di...
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Altera_Forum
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8 years ago

Hi, Anand,

1. Yes, I am sure that correct pins are probed.

2. 0.02 ohm is the value after Stratix V has been removed from the PCB. We probe on the Stratix V without PCB.

Today, we use X-ray to analyze another PCB with a mounted Stratix V on it. We found that the DNU pin is shorted to GND, because of the SMT process.

The "Pin Connection Guidelines" says "DNU: Do not connect to power, ground or any other signal. These pins must be left floating. "

In fact, those PCBs are never powered up, because of the short problem.

Is there possible that the FPGA is damaged when SMT-process short the DNU to GND?

Many Thanks,

Vina