MPX4100A
Sensors
Freescale Semiconductor 5
Pressure
On-chip Temperature Compensation and Calibration
Figure 2 illustrates an absolute sensing chip in the basic
chip carrier (Case 867). A fluorosilicone gel isolates the die
surface and wire bonds from the environment, while allowing
the pressure signal to be transmitted to the sensor
diaphragm. The MPX4100A series pressure sensor
operating characteristics, and internal reliability and
qualification tests are based on use of dry air as the pressure
media. Media, other than dry air, may have adverse effects on
sensor performance and long-term reliability. Contact the
factory for information regarding media compatibility in your
application.
Figure 3 shows the recommended decoupling circuit for
interfacing the output of the integrated sensor to the A/D input
of a microprocessor or microcontroller. Proper decoupling of
the power supply is recommended.
Figure 4 shows the sensor output signal relative to
pressure input. Typical, minimum, and maximum output
curves are shown for operation over a temperature range of
0° to 85°C using the decoupling circuit shown in Figure 3.
(The output will saturate outside of the specified pressure
range.)
Figure 2. Cross-Sectional Diagram (not to scale)
Figure 3. Recommended Power Supply Decoupling and Output Filtering
(For output filtering recommendations, refer to Application Note AN1646.)
Figure 4. Output versus Absolute Pressure
Absolute Element
P2
Lead Frame
Wire Bond
Fluoro Silicone
Gel Die Coat
Bond
Die
Epoxy Plastic
Case
Stainless Steel
Metal Cover
+5 V
1.0 μF
0.01 μF
470 pFGND
V
s
V
out
IPS
Output
Output (Volts)
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
Transfer Function:
V
OUT
= V
S
* (.01059*P-0.1518) ± Error
VS = 5.1 Vdc
Pressure (ref. to sealed vacuum) in kPa
MAX
TYP
MIN
5.0
4.5
3.5
4.0
3.0
2.5
2.0
1.5
1.0
0
0.5
TEMP = 0 to 85°C
20 kPa to 105 kPa
MPX4100A
