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Altera_Forum
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14 years ago

CPLD Weak pull-up resistors during power-up

All, There is mention in the MAX II device handbook of Weak pull-up resistors during power-up of the device. What I cannot find is the value of these weak pull-ups, does anyone know what the...
Altera_Forum's avatar
Altera_Forum
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14 years ago

Thanks for reminding the 300 uA specification. It has been added with later releases of the Device Handbook and I wasn't aware of it when answering the question. Taking the specification strictly, minimum Rpu is 11k during configuration and 5k in user mode with VCCIO of 3.3V. I'm not convinced, that the specification really indicates different resistance values, I'll check it with a MAX II device occasionally. 300 uA is more convenient however, because it allows higher pull-down resistor values for forced low-level.