Demand analysis: clarify the functional requirements, performance indicators, environmental adaptability, etc. of IOT devices. Hardware selection: select appropriate microcontrollers (MCU), sensors, actuators, communication modules, etc. according to the requirements. Circuit design: design circuit schematics, including power circuits, signal acquisition circuits, processing circuits, communication circuits, etc. Simulation verification: use circuit simulation software to simulate the circuit and verify the correctness of the design. PCB layout and wiring: convert the circuit schematic into a PCB layout diagram, and perform wiring design to ensure signal integrity and electromagnetic compatibility. Test and debugging: make PCB boards, perform welding, testing, and debugging to ensure the normal operation of the equipment.