Zero false alarm rate, Real-time response Correct data Minimum distinguishable particle diameter: 0.3 micrometer High anti-interference performance due to six-sided shielding patent structure Optional direction of air inlet and outlet to adapt to different designs PIN1: VCC power supply 5V PIN2: GND power ground PIN3: NC PIN4: RXD: Serial port receiving pin (3.3V level) PIN5: TXD: Serial port sending pin (3.3V level) PIN6: RESET (suspended during use; lowering causes module malfunction) PIN7: NC PIN8: PWM: Pulse width signal output pin (3.3V level) Circuit design注意事项: 1) D9 requires 5V power supply as the fan needs 5V drive. Data communication and control pins require 3.3V high level. The main board MCU connected for communication should be powered by 3.3V. If the MCU is 5V-powered, a level conversion chip or circuit must be added on communication lines (RXD, TXD) and control lines (SET, RESET). 2) For serial output, only connect PIN1, PIN2, PIN5; other pins not required. 3) For PWM output, only connect PIN1, PIN2, PIN8; other pins not required. Color: Silver Material: Metal Package Contents: 1 x Sensor Module (Other products not included) Note: Light reflection and display differences may cause slight color variation between image and actual item. Measurement error allowance: +/- 1-3 cm.