MPX2010

Sensors

Freescale Semiconductor

5

LINEARITY

Linearity refers to how well a transducer's output follows

pressure range. There are two basic methods for calculating

nonlinearity: (1) end point straight line fit (see Figure 4) or

(2) a least squares best line fit. While a least squares fit gives

the “best case” linearity error (lower numerical value), the

calculations required are burdensome.

Conversely, an end point fit will give the “worst case” error

(often more desirable in error budget calculations) and the

calculations are more straightforward for the user.

Freescale’s specified pressure sensor linearities are based

on the end point straight line method measured at the

midrange pressure.

Figure 4. Linearity Specification Comparison

PRESSURE (P1)/VACUUM (P2) SIDE IDENTIFICATION TABLE

Freescale designates the two sides of the pressure sensor

as the Pressure (P1) side and the Vacuum (P2) side. The

Pressure (P1) side is the side containing silicone gel which

isolates the die from the environment. The Freescale MPX

pressure sensor is designed to operate with positive

differential pressure applied, P1 > P2.

The Pressure (P1) side may be identified by using the

following table.

Least

Square

Deviation

Pressure (% Full Scale)

0

50

100

End Point Straight

Line Fit

Exaggerated

Performance

Curve

Least Squares Fit

Offset

Straight Line

Deviation

Table 3. Pressure (P1) Side Delineation

Part Number

Case Type

Pressure (P1) Side Identifier

MPX2010D

344

Stainless Steep Cap

MPX2010DP

344C

Side with Part Marking

MPX2010GP

344B

Side with Port Attached

MPX2010GS

344E

Side with Port Attached

MPX2010GSX

344F

Side with Port Attached

MPXV2010GP

1369

Side with Port Attached

MPXV2010DP

1351

Side with Part Marking