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Altera_Forum
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13 years ago

can't find the reason Stratix IV GX short-circuited between VCC and GND

hello everyone: i have some questions about Stratix IV GX the first time we configurate the FPGA in jtag, it's display configurate failed at 90%。We check the pcb and find that three pull-...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

According to the handbook, VCCPT is one of the supplies monitored by the power-on reset circuit. If it is not powered, then your FPGA will not exit POR, so any JTAG accesses will fail.

Try to determine if the power supply is bad. For example, ideally the supply was designed with a ferrite bead on its output. Remove that bead and see if the supply comes up ok. If it does, then you have to determine why it fails with the FPGA as a load. Have you rated the supply correctly, i.e., can it deliver enough current?

Cheers,

Dave