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sgx_sensortech_mics_series [17-06-2015 12:13]
philspaceindustries
sgx_sensortech_mics_series [06-08-2015 09:24] (current)
admin
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 Tips for designing with MICS sensors:​\\ ​ Tips for designing with MICS sensors:​\\ ​
-The labelled gasses for the sensors are merely those that the sensor is most affected by - cross sensitivity is an issue, as is interference from temperature and humidity. An accurate sensor system will need an array of these devices and calibration in order to be useful in measuring concentration of a specific gas.\\  +  * The labelled gasses for the sensors are merely those that the sensor is most affected by - cross sensitivity is an issue, as is interference from temperature and humidity. An accurate sensor system will need an array of these devices and calibration in order to be useful in measuring concentration of a specific gas.\\  
-MICS sensors vary significantly between examples in the same series. Each instrument using them must be individually calibrated.\\  +  ​* ​MICS sensors vary significantly between examples in the same series. Each instrument using them must be individually calibrated.\\  
-The heating element of almost all the MICS sensors require voltages of less than 2.4V across them to get the correct temperature. In the datasheet the suggested circuits use a 5V supply and simply dissipate off the excess voltage with a resistor. However, by using a simple step-down DC DC converter (like, say, the LM3671) you can drop the voltage with high efficiency, cutting current draw from your sensor array by half.\\  +  ​* ​The heating element of almost all the MICS sensors require voltages of less than 2.4V across them to get the correct temperature. In the datasheet the suggested circuits use a 5V supply and simply dissipate off the excess voltage with a resistor. However, by using a simple step-down DC DC converter (like, say, the LM3671) you can drop the voltage with high efficiency, cutting current draw from your sensor array by half.\\  
-The sensors require stable voltages on the heating element for a long time (over 30 minutes) to be reliable. Critically, even a seconds-long interruption in power can mean you must wait out their start-up time again. Be aware of how long you've had your sensor box powered up before you start trusting its measurements.\\ ​+  ​* ​The sensors require stable voltages on the heating element for a long time (over 30 minutes) to be reliable. Critically, even a seconds-long interruption in power can mean you must wait out their start-up time again. Be aware of how long you've had your sensor box powered up before you start trusting its measurements.\\ ​
sgx_sensortech_mics_series.txt · Last modified: 06-08-2015 09:24 by admin