Application Note SM-UART-04L Laser Dust Sensor SM-UART-04L Laser Dust Sensor is designed to operate in a moderate environment and provides excellent performance. Its embedded optical design leverages the strength from laser technology, which allows customers to achieve excellent performance with balanced reliability. SM-UART-04L is an ideal solution for industrial and consumer applications. SM-UART-04L laser dust sensor detects dust particle concentration in air by using an optical sensing method. A laser light emitting diode (laser LED) and a photo sensor are optically arranged in the device. The photo sensor detects the reflected laser LED light by dust particles in air. The dust sensor can detect small particles such as, cigarette smoke and distinguish small particles, such as smoke from large house dust, by the pulse pattern of the signal output. Features Applications Laser Optical Dust Indoor Air Quality Monitoring - High Accuracy Air Cleaners and Purifiers - Fast Response Air Conditioners and HVAC UART Output Outdoor Dust Monitoring Compact in Size Flexible Mounting Style Amphenol Advanced Sensors Figure 1 : Detection PrincipleSM-UART-04L Laser Dust Sensor Block Diagram Calibration Calibration carried out with cigarette smoke per GB/T1880 Absolute Maximum Ratings Absolute Maximum Ratings Parameter Symbol Rating Unit Supply Voltage Vcc 0 to + 5.5 V Operating Temperature Topr -10 to 50 C Storage Temperature Tstg -30 to 70 C (1) Operating Humidity RHopr 0 to 95 % (1) Storage Humidity RHstg 0 to 95 % 1) Non-condensing Electrical Characteristics Parameter Symbol Min. Typ. Max. Unit Particle Size D 0.3 2.5 10 um 3 Detection Range D 1 999 g/m reg 3 Resolution R 1 g /m 3 3 1 ~100 ug/m +/-10 g /m (2) Indication Error D err 3 100~999 ug/m +/-10 % (2) Warm-Up Time t 5 s wup (2) Response Time t 1 s rsp Average Trouble-free Working Time T 40000 hour Supply Voltage V 4.8 5 5.2 V CC Supply Voltage Ripple V Ripple 30 mV CC (2) Current Consumption I 60 100 mA CC Output (UART) 3.3V 1) Non-condensing 2) Testing at T=25C, RH=40-60% 2 Amphenol Advanced Sensors