3 Temperature Non Linearity

Due to the inherent properties of the bandgap PTAT (Proportional To Absolute Temperature) temperature sensor specifications, the temperature output signal is not fully linear. For improved accuracies in extreme temperatures please use the following formula:
T3T21

fSOdSOdd e Temperatur )(

2 with d
1 and d
2 as specified in the SHTxx datasheet page 5.
SO T d 3 [°C] f 14bit -2e-87000 12bit -3.2e-71750 This results in a correction of about -1°C at –40°C or 100°C compared to the linear formula.

4 Revision History

Date Revision Changes October 20, 2001 0.9 (Preliminary) February 10, 2002 1.0modified to final coefficients February 15, 2003 1.1added Temperature information Oct. 17, 2003 1.2Changed download link May 10, 2004 1.3 Added Temperature non linearity information October 19, 2004 1.31 Added 16 bit information in chapter 2.2 May 25, 2005 1.32 Changed company address Oct 3, 2006 1.4 Sensirion Inc. address added The latest version of this document and all application notes can be found at: www.sensirion.com/humidity

Headquarters and Sales Office

SENSIRION AG Phone: + 41 (0)44 306 40 00 Laubisrütistr. 50 Fax: + 41 (0)44 306 40 30 CH-8712 Stäfa ZH e-mail: info@sensirion.com Switzerland http://www.sensirion.com/ SENSIRION Inc Phone: 805-409 4900 Westlake Pl. Ctr. I, suite 240 Fax: 805-435 0467 2801 Townsgate Road e-mail: michael.karst@sensirion.com Westlake Village, CA 91361 http://www.sensirion.com/ USA
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