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Altera_Forum
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13 years ago

JTAG/IO Clamping and Hot-swapping

I am putting Cyclone IV GX on a new board that will be configured using PS. Since all the VCCIOs are 3.3V, I am planning on clamping the the JTAG and PS config signals using a pair of schottkys betw...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

Unfortunately, the other side of the backplane is already done and provides all the needed voltages (but no 1V or 3.0V). There is no space on the new board to add LDOs for that.

Probably I can use the tinylogic and add current limiting resistors on their output (they drive out up to 24mA). I can put the chip within 1" of the FPGA, so there may not be any issues with over/undeshoot. With this, I will not need clamping diodes. Does that make sense?