MQ-2 - Smoke Gas LPG Butane Hydrogen Gas Sensor

Electrical performance:
Input voltage: DC5V power consumption (current): 150mA
DO Output: TTL digital 0 and 1 (0.1 and 5V)
AO Output: 0.1-0.3V (relatively no pollution), the maximum concentration of about 4V voltage
Special reminder: the sensor power, the need to preheat 20S or so, the measured data was stable, the sensor fever is a normal phenomenon, because the internal electric wire, if the hot is not normal.

Wiring:
1, VCC: then the power supply positive (5V)
2, GND: Connect the power supply negative
3, DO: TTL switch signal output
4, AO: Analog signal output