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  1. Parts
  2. /Sensors
  3. /Gas & air quality

MQ135

OverviewWiringAlternates
MQ135 - Opencircuit - 10365

MQ-135 air quality sensor module for detecting harmful gases in air. Opencircuit lists analog output plus adjustable digital threshold output, 5±0.2V warm-up voltage, 150mA warm-up current, and 300–5000ppm detection range.

Parts tray full · 5 max · remove a part to add another
MQ135 — Opencircuit — 10365

Offers

  • ?OpenCircuit

Offers

  • ?OpenCircuit

Pinout

  • VCC

    5V module supply. Opencircuit lists 5±0.2V warm-up voltage and 150mA warm-up current.

    Type · powerVoltage · 5
  • GND

    Common ground.

    Type · ground
  • AOUT

    Analog gas concentration output.

    Type · analog
  • DOUT

    Comparator digital output with adjustable trigger concentration.

    Type · digital
PinPositionTypeFunctionVoltage
VCCpower5V module supply. Opencircuit lists 5±0.2V warm-up voltage and 150mA warm-up current.5
GNDgroundCommon ground.
AOUTanalogAnalog gas concentration output.
DOUTdigitalComparator digital output with adjustable trigger concentration.

Start wiring

I2C · Analog · UART · 3.3 – 5 V · Breakout

Waveshare lists MQ-2 for combustible gases and smoke, MQ-3 for alcohol, and MQ-135 for mixed indoor pollutants such as NH3, NOx, alcohol,…

Module pins: VCC, GND, AOUT, DOUT. Schematik maps them to your board in the app.

Air quality

106 other options

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