Sensors
4 Freescale Semiconductor
MPXAZ4100A
Figure 2 illustrates an absolute sensing chip in the basic
chip carrier (Case 482).
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.
A gel die coat isolates the die surface and wire bonds from
the environment, while allowing the pressure signal to be
transmitted to the sensor diaphragm. The gel die coat and
durable polymer package provide a media resistant barrier
that allows the sensor to operate reliably in high humidity
conditions as well as environments containing common
automotive media. Contact the factory for more information
regarding media compatibility in your specific 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 2. Cross Sectional Diagram SOP
(not to scale)
Figure 3. Recommended Power Supply Decoupling and Output Filtering
(For additional output filtering, please refer to Application Note AN1646.)
Figure 4. Output versus Absolute Pressure
Fluoro Silicone
Gel Die Coat
Wire Bond
Lead Frame
Sealed Vacuum Reference
Absolute Element
Die Bond
Stainless Steel Cap
Thermoplastic Case
P1
Die
+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
MAX
TYP
MIN
5.0
4.5
3.5
4.0
3.0
2.5
2.0
1.5
1.0
0
0.5
Pressure (ref: to sealed vacuum) in kPa
Transfer Function:
V
out
= V
s
* (.01059*P-.152) ± Error
V
S
= 5.1 Vdc
Temperature = 0 to 85°C
20 kPa TO 105 kPa
MPXAZ4100A
