MCP23008 as Level Shift I/O Expander?

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labrat9876
 
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MCP23008 as Level Shift I/O Expander?

Post by labrat9876 »

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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adafruit_support_bill
 
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Re: MCP23008 as Level Shift I/O Expander?

Post by adafruit_support_bill »

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

labrat9876
 
Posts: 6
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Re: MCP23008 as Level Shift I/O Expander?

Post by labrat9876 »

Awesome, Thank you so much for the help!

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