Adopt high-quality double-panel design with power indicator and TTL signal output indicator. Features DO switch signal (TTL) output and AO analog signal output. TTL output provides high and low level signals, compatible with microcontroller or relay module. Analog output voltage varies with gas concentration, offering fast response and recovery. Designed for long service life and reliable stability. Electrical specifications: Input voltage: DC 5V Power consumption: 150mA DO output: TTL digital signal (0 and 1, 0.1V and 5V) AO output: Analog level signal Note: After powering on the sensor, allow approximately 20 seconds for preheating to ensure stable readings. It is normal for the sensor to generate heat during operation due to the internal heating element. Wiring instructions: 1. VCC: Connect to positive terminal of power supply (5V) 2. GND: Connect to negative terminal of power supply 3. DO: TTL switch signal output 4. AO: Analog signal output Color: Green Material: Metal Package includes: 1 x MQ136 Hydrogen Sulfide Sensor Module Note: Other items not included. Color may vary slightly due to lighting and display differences. Measurement error allowance: +/- 1-3 cm.