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MCP23008 as Level Shift I/O Expander?
Moderators: adafruit_support_bill, adafruit

MCP23008 as Level Shift I/O Expander?

by labrat9876 on Fri Feb 15, 2013 10:40 pm

Hi! Working on an Adruino Project that has a mix of 5v and 3.3v I/O needs, also requiring more than are available on the adruino itself. If I run the MCP23008 at 3.3V, with an I2C connection to the Arduino @ 5v. Will the MCP23008 I/O expander(3.3v) be able to tolerate the higher voltage (5v) on the I2C connection?

Thanks
Chris
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Re: MCP23008 as Level Shift I/O Expander?

by adafruit_support_bill on Sat Feb 16, 2013 8:06 am

Just connect your i2c pullup resistors to 3.3v instead of 5v.

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Re: MCP23008 as Level Shift I/O Expander?

by labrat9876 on Tue Feb 26, 2013 12:08 pm

Awesome, Thank you so much for the help!
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