27901 Parallax Inc, 27901 Datasheet
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27901
Specifications of 27901
Related parts for 27901
27901 Summary of contents
Page 1
... TTL compatible output (ALR) Operating temperature 122 °F (-10 to 50°C) Dimensions: 1.50 x 1.0 x 1.0 in (38.1 x 25.4 x 25.4 mm) Copyright © Parallax Inc. Gas Sensor Modules (#27930, #27931, #27932, #27904) Web Site: www.parallax.com Forums: forums.parallax.com Sales: sales@parallax.com Technical: support@parallax.com Application Ideas ...
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... Switching circuit for the Propeller chip. Note: HIGH signal is required to turn on heater due to inversion of signal by the transistor. Copyright © Parallax Inc. Gas Sensor Modules (#27930, #27931, #27932, #27904) v2.2 8/2/2010 Page chip, a 3.9 kΩ (10 kΩ could be used) resistor would be TM ...
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... R4 the red LED will light and the ALR output will be high (5 V). The section below describes how to configure these gas sensor modules to detect gas with minimal calibration. Copyright © Parallax Inc. Gas Sensor Modules (#27930, #27931, #27932, #27904) v2.2 8/2/2010 Page Function ...
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... Note: Temperature and humidity are factors that could affect the sensor, making calibration difficult. If this should happen try adjusting the voltages used in the calibration up or down as necessary to find a more stable range. Copyright © Parallax Inc. Gas Sensor Modules (#27930, #27931, #27932, #27904) v2.2 8/2/2010 Page Please note that turning the ...
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... Go to http://www.parallax.com, type the specific product number into our search box and click “GO.” For gas calibration information you can also visit the following PDF on this website: http://www.gotgas.com/pdf/GasSnsrCalibratn.pdf Copyright © Parallax Inc. Gas Sensor Modules (#27930, #27931, #27932, #27904) v2.2 8/2/2010 Page ...
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... ELSE DEBUG " ENDIF LOOP UNTIL index = 0 LOOP Copyright © Parallax Inc. Gas Sensor Modules (#27930, #27931, #27932, #27904) v2.2 8/2/2010 Page The sensor should run for at The DEBUG screen will count down the 60 seconds ' Heater Switch Control ' Alarm Input Sense ...