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Altera_Forum
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9 years ago

Set undriven outputs to VCC / GND

Hello, Does exist some option that allows to set all unused outputs to VCC/GND ? Thanks.
Altera_Forum's avatar
Altera_Forum
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9 years ago

During configuration most FPGA devices will drive any outputs to the high impedance state, possibly with a very small pullup current source connected (ie, they don't really 'float').

There are set options to drive unused outputs low but this is not a direct, low impedance connection to GND, but just the output driving a low at a 10-25ma current or so.

I have never seen any device from any vendor that allows a pin to be programmatically connected direct to VCC or GND as if it were a power pin, for the reasons cited by the previous poster.