What this key-switch controller does on the board
The Analog Devices MAX7370ETG+ is a dedicated key-switch controller that offloads keypad scanning from the main MCU over an I2C interface. It handles up to a matrix of keys, debounces them, and presents the result as a logic-level output — no firmware polling loop needed. The 50 µA supply current makes it a fit for battery-powered or always-on front panels where every microamp counts.
