Download ML610Q400 Series Sample Program AP Notes For Barometer

3.1.2.4. Temperature Dependence of Voltage Difference
The voltage difference of the air pressure sensor changes, depending on temperature. Therefore, the temperature
correction is necessary for accurate measurement. The temperature characteristic of the sensor is described below.
The air pressure at the temperature T°C is calculated from Pressure - Voltage difference characteristic at 25°C by using
the following equation.
V25(T, Vt) = Vt / (1 + Kt(T))
V25(T, Vt)
Vt
Kt(T)
... （3.1.2.4-1）
: Voltage difference at 25°C, converted from voltage difference at T°C
: Voltage difference at T°C
: Temperature correction value
Kt(T) = A× (T - 25)2 + B × (T - 25)2
A = 6.88 ×10 -6
B = -7.41 ×10 -5
Press_t(T) = (V25(T,Vt) + Intercept25) / Slope25
Press_t(T)
Slope25
Intercept25
... （3.1.2.4-2）
: Air pressure at T°C
: Slope of Pressure - Voltage difference characteristic at 25°C
: Intercept of Pressure - Voltage difference characteristic at 25°C
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