Customer:
I’m working with the IO Expander MCP23017 (333007) for GPIO applications. I’ve observed that the SDA and SCL lines are not connected directly to pins 13 and 12 of the MCP23017. Could you provide the detailed schematic for this product?
Originally submitted via email support on 28 May 2025. Migrated to the forum for community visibility.
Soldered Support:
The hardware files are available at GitHub - SolderedElectronics/IO-expander-MCP23017-breakout-hardware-design: Hardware design, BOM, gerbers and 3D files for IO-expander-MCP23017-breakout designed by Soldered Electronics. · GitHub. You can find the schematic in the OUTPUTS folder.
The additional connections you may have found are likely the voltage regulators. Over the easyC/qwiic cable, the connection is 3V3. Over the header pins, it’s interchangeable 3V3/5V logic level.