Custom Raspberry Pi Compute Module 3 (CM3) I/O board Interface Adapter Board,CMIO V3.0 Original board Manufacturer

The Compute Module IO Board V3 is designed for use with the Raspberry Pi Compute Modules:
• CM1
• CM3
• CM3+8GB
• CM3+16GB
• CM33+32GB
• CM3LITE
• CM3+LITE
This I/O breakout board plugs onto the Compute Module to provide access to various ports that you would see on the traditional Raspberry Pi boards.

Why do I need one? You can use the CM3 I/O board as an adapter to get your Compute Module set up. The Compute Modules themselves do not have connectors on board, they are designed to be embedded into applications. That's where the CM3 I/O board comes in handy. It has all of the things that are harder to add, all on the board already. There is also the ability to add additional components if and when you need them.

The schematic diagram and design files of the Compute Module lO expansion board and the details of the connection between the SODIMM slot and the IO expansion board can be obtained from the following website: https://www.raspberrypi.org/documentation/hard-ware/computemodule/