The AB0204 module has four microphones arranged in a linear array for developers of audio beamforming applications. It is phantom powered over the A2B bus so does not need any external supply.
Unlike the I/O expansion boards that plug in to the Clockworks A2B OEM module the AB0204 is a complete A2B board. What is lost from the mix and match plug together nature of the other modules is gained in the small size and thin form factor that make this module ideal for creating prototype systems inside of actual products.
While the board does not have the extra expansion capability of the plug together systems the AB0204 does offer four GPIO lines, I2C, and 1.8V power to wire in additional functions. There is also a GPIO connected LED to provide visual feedback to a user or to locate a specific board during development.
Depending on use case 5 or 6 boards can be powered from one locally powered node. If using all 4 microphones on the board a system can have up to 8 boards for 32 microphones. An additional locally powered node must be added for an 8 node system to provide power. Clockworks AB0106 (with Ab0003 module) can serve that purpose.
Not all microphones need to be active a node which allows for a wide range of system microphone placements.
AB0204 quad linear array A2B microphone datasheet
AB0204 User manual (includes schematic)
A2B is a trademark of Analog Devices Inc.