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Altera_Forum
Honored Contributor
Honored ContributorCyclone III not configuring
I have a 144 pin cyclone 3 that I'm trying to get working in a board design I've done. It is not configuring. I can see the TCK on the oscilloscope but no TDO data comes back from the FPGA.
The nConfig and nStatus pins are both high and the CONF_DONE flag is low. I went through the altera trouble shooter but with no luck. One issue is that a ground pin and VCCA pin were shorted together when I first put the chip on the board. It got really hot when I turned it on and the voltage levels were screwed up. I'm not sure if I fried the chip. CONF_DONE is pulled high with a 10k resistor so the fact that it is low made me think the chip was still good. I've ordered some more chips and I'll try them out if I figure something else out first. Thanks.13 Replies
Altera_ForumIt does make a difference. It's the main Ground connector for the IC. I know one guy who put a large hole in the board centered on that pad just so he could get a soldering tip in there.
Jake- Altera_Forum
It is the TQFP. I tried to feed solder through the vias below the pad, so I'm not sure if it's actually connected. I could redo the board with paste. Does it make a difference electrically or is it just a heat sink?
- Altera_Forum
Well I would certainly suspect a fried chip. Aside from that, this must be the TQFP package. Did you solder the ground slug on the bottom of the IC?
Jake
