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Altera_Forum's avatar
Altera_Forum
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8 years ago

nStatus held low Cyclone IV EP4CE6E22

Hi, I've designed a board with a Cyclone IV EP4CE6E22. I have a problem with the config on the JTAG chain. My device is not detected. I've checked all Vcc (I/O=3.3V, PLLA = 2.5V, VccINT= ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
8 years ago

The package you're using has a GND pad on the bottom of it. Is that electrically connected to your PCB?

From the datasheet:

--- 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 of your PCB. Use this exposed pad for electrical connectivity and not for thermal purposes.

--- Quote End ---

There are quite a few posts on this forum relating to exactly this. Not connecting does cause problems - like yours.

Cheers,

Alex