MOTOROLA
SEMICONDUCTOR TECHNICAL DATA
Order this document
by MPX50/D
50 kPa
Uncompensated
Silicon Pressure Sensors
The MPX50 silicon piezoresistive pressure sensor provides a very accurate and linear
voltage output — directly proportional to the applied pressure. This standard, low cost,
uncompensated sensor permits manufacturers to design and add their own external
temperature compensating and signal conditioning networks. Compensation techniques
are simplified because of the predictability of Motorola’s single element strain gauge
design.
Features
•
Low Cost
•
Patented Silicon Shear Stress Strain Gauge Design
•
Ratiometric to Supply Voltage
•
Easy to Use Chip Carrier Package Options
•
60 mV Span (Typ)
•
Differential and Gauge Options
• ±
0.25% (Max) Linearity
Application Examples
•
Air Movement Control
•
Environmental Control Systems
•
Level Indicators
•
Leak Detection
•
Medical Instrumentation
•
Industrial Controls
•
Pneumatic Control Systems
•
Robotics
Figure 1 shows a schematic of the internal circuitry on the stand–alone pressure
sensor chip.
PIN 3
+ VS
PIN 2
+ Vout
X–ducer
PIN 4
– Vout
PIN 1
1
2
MPX50
SERIES
0 to 50 kPa (0 – 7.25 psi)
60 mV FULL SCALE SPAN
(TYPICAL)
BASIC CHIP
CARRIER ELEMENT
CASE 344–15, STYLE 1
DIFFERENTIAL
PORT OPTION
CASE 344C–01, STYLE 1
NOTE: Pin 1 is the notched pin.
PIN NUMBER
Gnd
+Vout
3
4
VS
–Vout
Figure 1. Uncompensated Pressure Sensor Schematic
VOLTAGE OUTPUT versus APPLIED DIFFERENTIAL PRESSURE
The differential voltage output of the X–ducer is directly proportional to the differential
pressure applied.
The output voltage of the differential or gauge sensor increases with increasing
pressure applied to the pressure side (P1) relative to the vacuum side (P2). Similarly,
output voltage increases as increasing vacuum is applied to the vacuum side (P2)
relative to the pressure side (P1).
Senseon and X–ducer are trademarks of Motorola, Inc.
REV 5
Motorola Sensor Device Data
©
Motorola, Inc. 1997
1
MPX50 SERIES
MAXIMUM RATINGS
Rating
Overpressure(8) (P1 > P2)
Burst Pressure(8) (P1 > P2)
Storage Temperature
Operating Temperature
Symbol
Pmax
Pburst
Tstg
TA
Value
200
500
– 40 to +125
– 40 to +125
Unit
kPa
kPa
°C
°C
OPERATING CHARACTERISTICS
(VS = 3.0 Vdc, TA = 25°C unless otherwise noted, P1 > P2)
Characteristic
Pressure Range(1)
Supply Voltage(2)
Supply Current
Full Scale Span(3)
Offset(4)
Sensitivity
Linearity(5)
Pressure Hysteresis(5) (0 to 50 kPa)
Temperature Hysteresis(5) (– 40°C to +125°C)
Temperature Coefficient of Full Scale Span(5)
Temperature Coefficient of Offset(5)
Temperature Coefficient of Resistance(5)
Input Impedance
Output Impedance
Response Time(6) (10% to 90%)
Warm–Up
Offset Stability(9)
Symbol
POP
VS
Io
VFSS
Voff
∆V/∆P
—
—
—
TCVFSS
TCVoff
TCR
Zin
Zout
tR
—
—
Min
0
—
—
45
0
—
– 0.25
—
—
– 0.22
—
0.21
400
750
—
—
—
Typ
—
3.0
6.0
60
20
1.2
—
±
0.1
±
0.5
—
±
15
—
—
—
1.0
20
±
0.5
Max
50
6.0
—
90
35
—
0.25
—
—
– 0.16
—
0.27
550
1800
—
—
—
Unit
kPa
Vdc
mAdc
mV
mV
mV/kPa
%VFSS
%VFSS
%VFSS
%VFSS/°C
µV/°C
%Zin/°C
Ω
Ω
ms
ms
%VFSS
MECHANICAL CHARACTERISTICS
Characteristic
Weight (Basic Element Case 344–15)
Common Mode Line Pressure(7)
Symbol
—
—
Min
—
—
Typ
2.0
—
Max
—
690
Unit
Grams
kPa
NOTES:
1. 1.0 kPa (kiloPascal) equals 0.145 psi.
2. Device is ratiometric within this specified excitation range. Operating the device above the specified excitation range may induce additional
error due to device self–heating.
3. Full Scale Span (VFSS) is defined as the algebraic difference between the output voltage at full rated pressure and the output voltage at the
minimum rated pressure.
4. Offset (Voff) is defined as the output voltage at the minimum rated pressure.
5. Accuracy (error budget) consists of the following:
•
Linearity:
Output deviation from a straight line relationship with pressure, using end point method, over the specified
pressure range.
•
Temperature Hysteresis: Output deviation at any temperature within the operating temperature range, after the temperature is
cycled to and from the minimum or maximum operating temperature points, with zero differential pressure
applied.
•
Pressure Hysteresis:
Output deviation at any pressure within the specified range, when this pressure is cycled to and from the
minimum or maximum rated pressure, at 25°C.
•
TcSpan:
Output deviation at full rated pressure over the temperature range of 0 to 85°C, relative to 25°C.
•
TcOffset:
Output deviation with minimum rated pressure applied, over the temperature range of 0 to 85°C, relative
to 25°C.
•
TCR:
Zin deviation with minimum rated pressure applied, over the temperature range of – 40°C to +125°C,
relative to 25°C.
6. Response Time is defined as the time for the incremental change in the output to go from 10% to 90% of its final value when subjected to
a specified step change in pressure.
7. Common mode pressures beyond specified may result in leakage at the case–to–lead interface.
8. Exposure beyond these limits may cause permanent damage or degradation to the device.
9. Offset stability is the product’s output deviation when subjected to 1000 hours of Pulsed Pressure, Temperature Cycling with Bias Test.
2
Motorola Sensor Device Data
MPX50 SERIES
TEMPERATURE COMPENSATION
Figure 2 shows the typical output characteristics of the
MPX50 series over temperature.
The X–ducer piezoresistive pressure sensor element is a
semiconductor device which gives an electrical output signal
proportional to the pressure applied to the device. This de-
vice uses a unique transverse voltage diffused semiconduc-
tor strain gauge which is sensitive to stresses produced in a
thin silicon diaphragm by the applied pressure.
Because this strain gauge is an integral part of the silicon
diaphragm, there are no temperature effects due to differ-
ences in the thermal expansion of the strain gauge and the
diaphragm, as are often encountered in bonded strain gauge
pressure sensors. However, the properties of the strain
gauge itself are temperature dependent, requiring that the
device be temperature compensated if it is to be used over
an extensive temperature range.
Temperature compensation and offset calibration can be
achieved rather simply with additional resistive components,
or by designing your system using the MPX2050 series
sensors.
Several approaches to external temperature compensa-
tion over both – 40 to +125°C and 0 to + 80°C ranges are
presented in Motorola Applications Note AN840.
LINEARITY
Linearity refers to how well a transducer’s output follows
the equation: Vout = Voff + sensitivity x P over the operating
pressure range (see Figure 3). There are two basic methods
for calculating nonlinearity: (1) end point straight line fit 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. Motorola’s
specified pressure sensor linearities are based on the end
point straight line method measured at the midrange
pressure.
70
100
90
80
70
OUTPUT (mVdc)
60
50
40
30
20
OFFSET
(TYP)
1
10
2
3
20
4
30
5
40
6
7
50
8
10
0
0
PRESSURE (kPA)
OFFSET
(VOFF)
MAX
POP
OUTPUT (mVdc)
MPX50
VS = 3 Vdc
P1 > P2
+ 25°C
– 40°C
50
ACTUAL
40
30
20
THEORETICAL
SPAN
(VFSS)
+ 125°C
SPAN
RANGE
(TYP)
60
LINEARITY
10
0
PSI 0
kPa 0
PRESSURE DIFFERENTIAL
Figure 2. Output versus Pressure Differential
Figure 3. Linearity Specification Comparison
SILICONE
DIE COAT
WIRE BOND
DIE
P1
STAINLESS STEEL
METAL COVER
EPOXY
CASE
LEAD FRAME
Figure 4. Cross–Sectional Diagram (not to scale)
Figure 4 illustrates the differential or gauge configuration
in the basic chip carrier (Case 344–15). A silicone gel iso-
lates the die surface and wire bonds from the environment,
while allowing the pressure signal to be transmitted to the sil-
icon diaphragm.
The MPX50 series pressure sensor operating characteris-
tics 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.
Motorola Sensor Device Data
ÉÉÉÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉÉÉÉ
P2
RTV DIE
BOND
3
MPX50 SERIES
PRESSURE (P1)/VACUUM (P2) SIDE IDENTIFICATION TABLE
Motorola 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 Motorola MPX
Part Number
MPX50D
MPX50DP
MPX50GP
MPX50GVP
MPX50GS
MPX50GVS
MPX50GSX
MPX50GVSX
Case Type
344–15
344C–01
344B–01
344D–01
344E–01
344A–01
344F–01
344G–01
pressure sensor is designed to operate with positive differen-
tial pressure applied, P1 > P2.
The Pressure (P1) side may be identified by using the
table below:
Pressure (P1) Side Identifier
Stainless Steel Cap
Side with Part Marking
Side with Port Attached
Stainless Steel Cap
Side with Port Attached
Stainless Steel Cap
Side with Port Attached
Stainless Steel Cap
ORDERING INFORMATION
MPX50 series pressure sensors are available in differential and gauge configurations. Devices are available with basic
element package or with pressure port fittings which provide printed circuit board mounting ease and barbed hose pressure
connections.
MPX Series
Device Type
D i T
Basic Element
Ported Elements
Options
O i
Differential
Differential
Gauge
Gauge Vacuum
Gauge Stovepipe
Gauge Vacuum Stovepipe
Gauge Axial
Gauge Vacuum Axial
Case Type
C
T
Case 344–15
Case 344C–01
Case 344B–01
Case 344D–01
Case 344E–01
Case 344A–01
Case 344F–01
Case 344G–01
Order Number
MPX50D
MPX50DP
MPX50GP
MPX50GVP
MPX50GS
MPX50GVS
MPX50GSX
MPX50GVSX
Device Marking
MPX50D
MPX50DP
MPX50GP
MPX50GVP
MPX50D
MPX50D
MPX50D
MPX50D
4
Motorola Sensor Device Data
MPX50 SERIES
PACKAGE DIMENSIONS
NOTES:
C
R
M
B
–A–
N
PIN 1
1
2
3
4
POSITIVE
PRESSURE (P1)
1. DIMENSIONING AND TOLERANCING PER ASME
Y14.5M, 1994.
2. CONTROLLING DIMENSION: INCH.
3. DIMENSION –A– IS INCLUSIVE OF THE MOLD
STOP RING. MOLD STOP RING NOT TO EXCEED
16.00 (0.630).
INCHES
MIN
MAX
0.595
0.630
0.514
0.534
0.200
0.220
0.016
0.020
0.048
0.064
0.100 BSC
0.014
0.016
0.695
0.725
30
_
NOM
0.475
0.495
0.430
0.450
MILLIMETERS
MIN
MAX
15.11
16.00
13.06
13.56
5.08
5.59
0.41
0.51
1.22
1.63
2.54 BSC
0.36
0.40
17.65
18.42
30
_
NOM
12.07
12.57
10.92
11.43
L
–T–
J
SEATING
PLANE
POSITIVE
PRESSURE
(P1)
G
F
4 PL
D
0.136 (0.005)
M
T A
M
DIM
A
B
C
D
F
G
J
L
M
N
R
STYLE 1:
PIN 1.
2.
3.
4.
GROUND
+ OUTPUT
+ SUPPLY
– OUTPUT
CASE 344–15
ISSUE W
PORT #2
VACUUM
PRESSURE
(P2)
C
POSITIVE
PRESSURE
(P1)
PIN 1
A
NOTES:
1. DIMENSIONING AND TOLERANCING PER ANSI
Y14.5M, 1982.
2. CONTROLLING DIMENSION: INCH.
DIM
A
B
C
D
F
G
J
K
N
R
S
V
INCHES
MIN
MAX
0.690
0.720
0.245
0.255
0.780
0.820
0.016
0.020
0.048
0.064
0.100 BSC
0.014
0.016
0.345
0.375
0.300
0.310
0.178
0.186
0.220
0.240
0.182
0.194
GROUND
+ OUTPUT
+ SUPPLY
– OUTPUT
MILLIMETERS
MIN
MAX
17.53
18.28
6.22
6.48
19.81
20.82
0.41
0.51
1.22
1.63
2.54 BSC
0.36
0.41
8.76
9.53
7.62
7.87
4.52
4.72
5.59
6.10
4.62
4.93
–B–
V
1 2
3 4
K
J
R
SEATING
PLANE
S
G
F
D
4 PL
0.13 (0.005)
M
N
–T–
T B
M
STYLE 1:
PIN 1.
2.
3.
4.
CASE 344A–01
ISSUE B
Motorola Sensor Device Data
5
