PRODUCT INFORMATION TGS 4161 - for the detection of Carbon Dioxide Features: Applications: * High selectivity to CO2 * Compact size * Low dependency on humidity * Long life and low cost * Low power consumption * Indoor air quality control * CO2 monitors TGS4161 is a new solid electrolyte CO2 sensor which offers miniaturization and low power consumption. A range of 350~10,000ppm of carbon dioxide can be detected by TGS4161, making it ideal for indoor air control applications. The CO2 sensitive element consists of a solid electrolyte formed between two electrodes, together with a printed heater (RuO2) substrate. By monitoring the change in electromotive force (EMF) generated between the two electrodes, it is possible to measure CO2 gas concentration. The top of the sensor cap contains adsorbent (zeolite) for the purpose of reducing the influence of interference gases. TGS4161 exhibits a linear relationship between EMF and CO2 gas concentration on a logarithmic scale. The sensor displays good long term stability and shows excellent durability against the effects of high humidity. The figure below represents typical sensitivity characteristics of TGS4161. The Y-axis is indicated as EMF which is defined as follows: The figure below shows typical humidity dependency of TGS4161. Again, the Y-axis is indicated as EMF which is defined as follows: EMF=EMF1 - EMF2 where EMF1=EMF in 350 ppm CO2 EMF2=EMF in listed gas concentration EMF=EMF1 - EMF2 where EMF1=EMF in 350 ppm CO2 EMF2=EMF in 1000ppm CO2 Humidity Dependency: Sensitivity Characteristics: 100 80 60 CO2 CO Ethanol H2 100 325 75 EMF (350ppm CO2) EMF (mV) 300 EMF (mV) 40 20 EMF (mV) 50 275 25 EMF (350ppm CO2 - 1000ppm CO2) 0 10 350 250 100 1000 Gas Concentration (ppm) 10000 10 20 30 40 50 60 70 80 90 0 Relative Humidity (%) IMPORTANT NOTE: OPERATING CONDITIONS IN WHICH FIGARO SENSORS ARE USED WILL VARY WITH EACH CUSTOMER'S SPECIFIC APPLICATIONS. FIGARO STRONGLY RECOMMENDS CONSULTING OUR TECHNICAL STAFF BEFORE DEPLOYING FIGARO SENSORS IN YOUR APPLICATION AND, IN PARTICULAR, WHEN CUSTOMER'S TARGET GASES ARE NOT LISTED HEREIN. FIGARO CANNOT ASSUME ANY RESPONSIBILITY FOR ANY USE OF ITS SENSORS IN A PRODUCT OR APPLICATION FOR WHICH SENSOR HAS NOT BEEN SPECIFICALLY TESTED BY FIGARO. Basic Measuring Circuit: The TGS4161 sensor requires heater voltage (VH) input. The heater voltage is applied to the integrated heater in order to maintain the sensing element at a specific temperature which is optimal for sensing. Electromotive force (EMF) of the sensor should be measured using a high impedance (>100 G) operational amplifier with bias current < 1pA (e.g. Texas Instruments' model #TLC271). Since the solid electrolyte type sensor functions as a kind of battery, the EMF value itself would drift using this basic measuring circuit. However, the change of EMF value (EMF) shows a stable relationship with the change of CO2 concentration. Therefore, in order to obtain an accurate measurement of CO2, a special microprocessor for signal processing should be used with TGS4161. Figaro can provide a special evaluation sensor module (AM-4-4161) for TGS4161. Specifications: Model number TGS 4161 Sensing element type Solid electrolyte Target gases Carbon dioxide Typical detection range 350 ~ 10,000 ppm Electrical characteristics Heater resistance RH 70 7 at room temp. Heater current IH approx. 50mA Heater power consumption PH approx. 250mW E MF 220~490mV in 350ppm CO2 Electromotive force Sensitivity EMF Heater voltage Sensor characteristics VH Response time Measurement accuracy 44~72mV EMF(350ppm CO2)EMF(3500ppm CO2) 5.0 0.2V (DC) Strorage conditions (store in moisture proof bag with silica gel) - VH EMF 4 3 TGS4161 GND Structure and Dimensions: Top view o9.20.2 o8.10.2 Sensing element 12.41.0 Side view -20~60C, 5~90%RH CO2 in air at 202C, 655%RH Circuit condition VH = 5.00.05V DC Conditioning period before test 12 hours or longer Sensing Element Structure: 2 approx. 20% at 1,000ppm CO2 -10~50C, 5~95%RH Standard test conditions + 1 approx. 1.5 min. (to 90% of final EMF value) Operating conditions Test gas condition Operational Amplifier IBIAS < typ. 1pA 10.01.0 o0.550.05 3.60.1 Bottom view 90 Pin Connection: 1. Heater (+) 2. Counter electrode (+) 3. Sensing electrode (-) 4. Heater (-) For information on warranty, please refer to Standard Terms and Conditions of Sale of Figaro USA Inc. REV: 12/05 4 3 1 2 3.6.1 o5.1 u/m = mm FIGARO USA, INC. 121 S. Wilke Rd. Suite 300 Arlington Heights, IL 60005 USA Phone: (1)-847-832-1701 Fax: (1)-847-832-1705 email: figarousa@figarosensor.com