Function: Controls the operation of the compressor, fan, and heating elements to maintain appropriate temperature.

Construction: Typically consists of a processor, circuit board, power module, etc.

Protection Mechanism: Built-in overload protection and short-circuit protection functions to prevent equipment damage.

User Interface: The main board is usually connected to the control panel of the refrigerator, allowing users to set temperature and modes.

Power Requirements: Typically requires a stable power supply to ensure proper operation.