TGS822 Ethanol Gas Sensor – Alcohol Vapor Detection Module

Description

The search results consistently refer to the Figaro TGS822 as a bare semiconductor sensor element, not a complete module with comparator and digital output . If your product is a breakout board (with LM393, potentiometer, and AO/DO outputs), it is a third-party module built around the TGS822 sensor, not a Figaro product. We strongly recommend verifying exactly what you are selling: the bare sensor, or a module. The specifications below reflect the bare TGS822 sensor as documented in the manufacturer datasheet, with notes on module-level features where applicable.

Long Description

The TGS822 is a tin dioxide (SnO₂) semiconductor gas sensor from Figaro, designed for detecting ethanol and other organic solvent vapors. Its sensing element uses an SnO₂ thick film sintered on an alumina ceramic tube containing an integrated heater. In clean air, the sensor exhibits low conductivity. When alcohol or organic solvent vapors are present, the sensor’s conductivity increases proportionally to gas concentration, allowing a simple circuit to convert this change into an output signal .

The sensor is highly sensitive to ethanol and widely used in alcohol checkers, breathalyzers, and industrial solvent detection. It features excellent long-term stability, a long service life, and can be operated with a simple electrical circuit . The recommended load resistor (RL) is 10kΩ for typical applications . The sensor requires a preheating period of more than 7 days before reliable measurement—this is a critical requirement that must be clearly stated to customers .

Critical limitation: The TGS822 responds to multiple organic solvents, not just ethanol. It is not a selective ethanol sensor and should not be used for quantitative breath alcohol measurement without calibration and cross-sensitivity compensation.

Features

• High Sensitivity to Ethanol and Organic Solvents: Optimized for alcohol vapor detection, widely used in breathalyzer and alcohol checker applications .

• Excellent Long-Term Stability: Figaro specifies high stability and reliability over extended operation .

• Simple Drive Circuit: Requires only heater voltage (VH) and circuit voltage (VC) with a load resistor .

• Low Sensor Power Dissipation: Sensor electrode power (Ps) must be kept at or below 15mW to prevent damage .

• Standard 6-Pin Package: Plastic housing with SUS316 double gauze flame arrestor .

• Wide Detection Range: 50–5,000 ppm ethanol .

• Long Service Life: Manufacturer-rated for extended operation with proper use.

• Preheat Required: Minimum 7 days energization before accurate measurement .

Technical Specifications