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Altera_Forum
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11 years ago

Cyclone III 144 QFP package forgot the ground pad on circuit board

Our circuit board guy forgot to put a ground pad on the board for the 144 pin package on the bottom of the chip. We are unable to detect it thru the JTAG port and assuming that is why. What may al...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

Shouldn't be very difficult to drill a hole and solder a wire to the pad, just make sure you don't drill into the chip :) Altera says you must ground the pad - from the CIII Handbook:

--- Quote Start ---

The E144 package has an exposed pad at the bottom of the package. This exposed pad is a ground pad that must be connected to the ground plane on your PCB. Use this exposed pad for electrical connectivity and not for thermal purposes.

--- Quote End ---

Also check the output of the 1.2V and 2.5V power regulators, just to make sure everything else is ok.