PCA9698BS Device Addressing

[ryan_smith]

Hi,

I am utilizing the PCA9698BS I/O Expander in a design. For this part's device address I have the external strapping setup for address 0x20. But when I try to talk to address 0x20 over the I2C bus, I detect no I2C bus devices. But I actually detect the I/O Expander I2C bus on address 0x10. When I write commands to this address I am able to fully communicate with the PCA9698BS device. Why does the datasheet specify that the address is 0x20 (for the external strapping that I'm using), when address 0x10 works instead?? The device address 0x10 isn't even an option within the PCA9698BS datasheet.

Thanks,

Ryan

[ryan_smith]

Hi Erika,

Thanks for sharing this post. It was my assumption that something such as bit shifting was happening. Thanks for confirming.

-Ryan

[ErikaC · Accepted solution]

Hello,

Can you please check this post: https://community.nxp.com/t5/Other-NXP-Products/IO-Expander-PCA9698-not-responding-to-I2C-Address/td...