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What happen if intermediate V applied if MCU pull up/down externally?

Latest Updated:05/24/2007

Question:

(Pin, I/O Port)  If the MCU ports are pulled up/down externally, or used as input ports without pin handling such as turning the pull-up transistor off internally, what will happen if an intermediate voltage is applied? [2007/05/24]

Answer:

Generally, the following can be said regarding the input ports indicated as "open" under "Connections of Unused Pins" in the datasheet. A penetrating current may flow between VDD and VSS while an input instruction is being executed, but the level of current will seldom be enough to damage the ports or the MCU. (#106676)
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