Greetings - I'm utilizing a MCP23017 @ 3.3v to monitor 16 bits of digital signaling. With the MCP23017 operating @ 3.3v would the inputs tolerate 5v? The datasheet states the GPIO Input High Voltage has a Max of Vdd, but there's a note to the side stating "For entire Vdd range". Simply trying to avoid level shifting the inputs or i2c bus and curious if anyone has utilized one a MCP23017 in this fashion before I send one up in smoke...
TIA,
-Terry
From the data sheet absolute maximums.
Voltage on all other pins with respect to VSS (except VDD)...........-0.6V to (VDD + 0.6V)
That says, to me, that the max input voltage, on any pin, with a 3.3V supply, is 3.9V.
groundFungus:
From the data sheet absolute maximums.Voltage on all other pins with respect to VSS (except VDD)...........-0.6V to (VDD + 0.6V)That says, to me, that the max input voltage, on any pin, with a 3.3V supply, is 3.9V.
Voltage on VDD with respect to VSS ... -0.3V to +5.5V
Voltage on all other pins with respect to VSS (except VDD)............................................................. -0.6V to (VDD + 0.6V)
That's how I read it also.
Ron
When using 3.3V parts, by far the best solution is to use a 3.3V Arduino. The 3.3V Pro Mini can be purchased for about $2 on eBay, and you never need to worry about level shifting.
Make sure that you use a 3.3V FTDI programming adapter! The 3.3V Arduino will work fine with a 5V FTDI adapter, but destroy the 3.3V module.
Like this one.
[FTDI Basic Breakout 5V/3.3V - Micro USB](http://"Product not found!" basic&filter_description="true&filter_sub_category=true&product_id=600")
3.3V from the FTDI (50mA), and 3.3V IO signals when the jumper is set.
Measure it to be sure.