MPX5700 SERIES

3

Motorola Sensor Device Data

ON–CHIP TEMPERATURE COMPENSATION, CALIBRATION AND SIGNAL CONDITIONING

Figure 3 illustrates both the Differential/Gauge and the Ab-

solute 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. (For use of the

MPX5700D in a high pressure, cyclic application, consult the

factory.)

The MPX5700 series pressure sensor operating character-

istics, 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 re-

garding media compatibility in your application.

Figure 4 shows a typical decoupling circuit for interfacing

the sensor to the A/D input of a microprocessor. Proper de-

coupling of the power supply is recommended.

Figure 2 shows the sensor output signal relative to pres-

sure input. Typical, minimum, and maximum output curves

are shown for operation over a temperature range of 0

° to

85

°C using the decoupling circuit below. (The output will sat-

urate outside of the specified pressure range.)

DIFFERENTIAL PRESSURE (kPa)

Figure 2. Output versus Pressure Differential

5.0

4.0

3.0

2.0

0

700

300

0

500

4.5

3.5

2.5

1.5

100

1.0

0.5

600

200

800

400

TYPICAL

TRANSFER FUNCTION:

Vout = VS*(0.0012858*P+0.04) ± ERROR

VS = 5.0 Vdc

TEMP = 0 to 85

°C

MAX

MIN

FLUORO SILICONE

DIE COAT

LEAD

FRAME

STAINLESS STEEL

METAL COVER

RTV DIE

BOND

DIE

EPOXY CASE

WIRE BOND

Figure 3. Cross–Sectional Diagram

(Not to Scale)

µ PROCESSOR

A/D

51 k

50 pF

MPX5700

OUTPUT

(PIN 1)

Figure 4. Typical Decoupling Filter for Sensor to

Microprocessor Interface

P1

P2