# Datasheets of the MQ Sensor Series

MQ-2: https://www.mouser.com/datasheet/2/321/605-00008-MQ-2-Datasheet-370464.pdf

MQ-3: https://www.mouser.com/datasheet/2/272/mq3-alcohol-sensor-datasheet-1864348.pdf

MQ-4: https://www.mouser.com/datasheet/2/830/MQ_4-2488748.pdf 
(https://www.mouser.com/datasheet/2/813/MQ-4_Ver1.3_-_Manual-1509240.pdf)

MQ-5: https://www.mouser.com/datasheet/2/830/MQ_5-2488317.pdf

MQ-6: https://www.mouser.de/datasheet/2/813/MQ-6_Ver1.3_-_Manual-1509296.pdf

MQ-7: https://www.mouser.com/datasheet/2/321/605-00007-MQ-7-Datasheet-370460.pdf

MQ-8: https://www.mouser.com/datasheet/2/830/MQ_8-1951103.pdf

MQ-9: https://www.mouser.com/datasheet/2/830/SEN0134_MQ_9-2488817.pdf

MQ-131: https://soldered.com/productdata/2021/01/Soldered_o3.winsen-mq131_datasheet.pdf (Ozone)

MQ-135: https://soldered.com/productdata/2022/03/Soldered_MQ-135_datasheet.pdf

MQ-135 Module: https://www.mouser.com/datasheet/2/1398/Soldered_333111-3395313.pdf

MQ-136: https://soldered.com/productdata/2023/09/Soldered_MQ136_datasheet.pdf (Hydrogen Sulfide (H2S)

MQ-136 Module: https://www.mouser.com/datasheet/2/1398/Soldered_333112-3395294.pdf

MQ-137: https://www.winsen-sensor.com/d/files/semiconductor/mq137.pdf (Ammonia NH3)

MQ-138: https://www.winsen-sensor.com/d/files/PDF/Semiconductor%20Gas%20Sensor/MQ138%20(Ver1.4)%20-%20Manual.pdf (VOC Gas, MQ138 gas sensor has high sensitivity to toluene, acetone,
alcohol, methanol, also can monitor hydrogen and other organic vapour well)

MQ-139: https://www.l-com.com/Images/Downloadables/Manuals/M_SRAQ-G021.pdf (Freon gases: R11, R22, R113, R134, R409A, R410A etc.)