5V tolerant with VDD at 3.3V

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disraelsen@camp...
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Last seen: 1 year 9 months ago
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5V tolerant with VDD at 3.3V

The datasheets indicate that the max input voltage for I/O pins is VDD + 0.3V. If VDD supply is 3.3V and a input pin has 5V applied, can this be tolerated if we add series resistance to limit the current through the protection diode of the input stage (protection circuitry)? If yes.... how much current can the protection diode tolerate.

Device: 
Device Number: 
Dual Supply GreenPAK SLG46880
pavloZ
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Last seen: 2 years 7 months ago
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Joined: 2018-01-31 12:50
Hi Disraelsen,

Hi Disraelsen,

Internal diodes dedicated to handle only ESD protection. You should use zener diode after serial resistance in your case, otherwise we can't guarantee device reliability. 

Thanks.