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Altera_Forum
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14 years ago

Cyclone IV GX bank 9 VCCIO

Just wondering if anyone can help.. I'm using a 4CGX150 with the JTAG pins (TDI, TDO etc.) dedicated to the usual 10 pin connector for JTAG programming. These pins are not used for any other IO...
Altera_Forum's avatar
Altera_Forum
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14 years ago

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Yes I'm aware of the ESD issues, I have series resistors in line to the device. I sometimes add a DALC208SC6 device to absorb any stray static. The tiny logic is a good suggestion, but I have the board layout complete, so next time.

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I prefer the TinyLogic parts rather than just ESD diodes, as they protect against an invalid voltage on the JTAG pins, eg. a 5V logic value from a non-standard JTAG programmer.

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I was more concerned about the VCCIO voltage, so I will go with +2.5V on pin G4 (VCCIO Bank 9) of the device.

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I had a further look at the handbook, and did not see any problems with using 2.5V for the JTAG.

Cheers,

Dave