Product Description: MH-Z19B carbon dioxide gas sensor (hereinafter referred to as the sensor) is a general-purpose smart small-scale sensor that uses non-dispersive infrared (NDIR) principle to detect the presence of CO2 in the air, with good selectivity and anaerobic Gas dependence, long life and other characteristics; built-in temperature compensation; at the same time with serial output, analog output and PWM output, easy to use. The sensor is a high-performance sensor that combines mature infrared absorption gas detection technology with precise optical path design and sophisticated circuit design.
Product Parameters: 1. Product model number: MH-Z19B 2. Gas Detection: Carbon Dioxide 3. Supply voltage: 4.5~5.5V DC 4. Average current: <20mA (@5V power supply) 5. Peak current: 150 mA (@5V supply) 6. Interface level: 3.3V (5V compatible) 7. Measurement range: 0~10000ppm can be selected within the range 8. Output signal: Serial (UART) (TTL level 3.3V) PWM Analog output (DAC) (default 0.4~2V) (0~3V range configurable) 9. Warm-up time: 3min 10. Response time: T90<120s 11. Working temperature: 050ﾣC 12. Operating Humidity: 0 to 95% RH (non-condensing) 13. Weight: 5g 14. Life: >5 years
Sensor Features: 1. Gas chamber with gold plating, waterproof and corrosion resistant 2. High sensitivity, low power consumption 3. Excellent stability 4. Temperature compensation, excellent linear output 5. Provides serial (UART), analog (DAC), PWM waveform output methods 6. long lasting 7. Water vapor interference, not poisoning
Application: HVAC refrigeration equipment Air quality monitoring equipment Fresh air system Air purification equipment Smart home SCHOOL
Pin Definition: 
Vin: Power Positive (Vin) GND: Negative Power Supply (GND) Vo: Analog output PWM: PWM HD: HD (zero for school, low for more than 7 seconds) Rx: UART(RXD) TTL Level Data Input Tx: UART (TXD) TTL level data output Pin 1: Analog Output Vo Pin 2: None Pin 3: Negative Power Supply (GND) Pin 4: Positive Power Supply (Vin) Pin 5: UART(RXD) TTL Level Data Input Pin 6: UART (TXD) TTL Level Data Output Pin 7: None
Package included: 1 xMH-Z19B carbon dioxide gas sensormodule with Terminal
