DEMOAPEXSENSOR Freescale Semiconductor, DEMOAPEXSENSOR Datasheet

BOARD DESIGN ALTITUDE PRESSURE

DEMOAPEXSENSOR

Manufacturer Part Number
DEMOAPEXSENSOR
Description
BOARD DESIGN ALTITUDE PRESSURE
Manufacturer
Freescale Semiconductor
Datasheet

Specifications of DEMOAPEXSENSOR

Sensor Type
Accelerometer, Pressure, Water Level, Altimeter/Barometer
Sensing Range
Multiple Ranges
Interface
I²C, SPI, Analog
Sensitivity
Multiple
Voltage - Supply
10 V
Embedded
Yes, MCU, 8-Bit
Utilized Ic / Part
MPX2102, MPXV5004G, MPL115A2, MMA7361L
Acceleration
6 g
Sensing Axis
Triple Axis
Output Type
Digital
Interface Type
I2C, SPI
Operating Voltage
16 V
Operating Current
10 mA
Leaded Process Compatible
Yes
Peak Reflow Compatible (260 C)
Yes
Rohs Compliant
Yes
Silicon Manufacturer
Freescale
Silicon Core Number
MPXM2102A, MPXV5004G, MPL115A2, MMA7361L
Kit Application Type
Sensing - Sampling Kit / Related Components
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
For Use With/related Products
MPL115A, MPXM102A, MPXV5004G
Freescale Semiconductor
Application Note
DEMOAPEXSENSOR Usage
Altitude Pressure EXperimental (APEX) Sensor Board
by: John B. Young
INTRODUCTION
demo. These include: Altimeter, Barometer, Barometer Alarm, Weather station, Waterlevel, Waterlevel Alarm, Tilt, Freefall, and
Temperature Sensing. The board has been designed as a standalone board to be interfaced currently via an LCD display and
menu buttons. The multiple functions of the Altitude Pressure EXperimental (APEX) Sensor board are possible with the use of
Freescale’s sensors. This kit has the following: MPL115A2, MPXM2102A, MPXV5004G pressure sensors with an MMA7361L
accelerometer. The demo makes use of Freescale’s Flexis MC9S08JM60 8-bit microcontroller.
DEMOAPEXSENSOR with important items highlighted. Freescale’s sensors are listed along with their associated application in
Table
© Freescale Semiconductor, Inc., 2009, 2010. All rights reserved.
Table 1. On-Board Sensors
MPL115A
MPXM2102A
MPXV5004G
MMA7361L
The DEMOAPEXSENSOR is an experimental sensor board focused on pressure with a variety of applications built into the
Device
1.
LCD Display
for Results
Pressure Absolute
Pressure Absolute
Development
Header
MPL115A
USB
Connector
Type of Sensor
Pressure Gauge
Accelerometer
BDM
Figure 1. Basic Components of APEX Board
Measurement Range of Sensor
Selectable ±1.5g, ±6g
50 - 115 kPa
0 - 100 kPa
0 - 4 kPa
Temperature Sensor
Altimeter/Absolute Pressure
Acceleration, Tilt, Shock,
Sensor Application
Barometer/Altimeter
Liquid Level Sensor
Freefall
MPXM2102A
Absolute Pressure
Sensor
Backside:
MPXV5004G
Gauge Pressure
Sensor-
MMA7361L
3 Axis low-g
Accelerometer
-Motion
Push Buttons
“Up, Down, ESC
Enter”
Figure 1
-Altitude
Waterlevel
is an image of the
Interface Type
Digital I
Rev 1, 09/2010
Analog
Analog
Analog
2
C/SPI
AN3956

Related parts for DEMOAPEXSENSOR

DEMOAPEXSENSOR Summary of contents

Page 1

... John B. Young INTRODUCTION The DEMOAPEXSENSOR is an experimental sensor board focused on pressure with a variety of applications built into the demo. These include: Altimeter, Barometer, Barometer Alarm, Weather station, Waterlevel, Waterlevel Alarm, Tilt, Freefall, and Temperature Sensing. The board has been designed as a standalone board to be interfaced currently via an LCD display and menu buttons. The multiple functions of the Altitude Pressure EXperimental (APEX) Sensor board are possible with the use of Freescale’ ...

Page 2

... Menu Buttons Figure simplified block diagram of the DEMOAPEXSENSOR. The sensors with analog outputs via the JM60 microcontroller’s 12-bit ADC. The exception is the MPXM2102A absolute pressure sensor. This is used for altitude so it requires a high resolution sampling. It passes through an instrumentation amplifier and then is interfaced via an external 24-bit ADC chipset before communication via SPI to the JM60 MCU ...

Page 3

... Sensors Freescale Semiconductor Figure CH3 44 43 CH2 42 41 CH1 40 39 CH0 38 37 PTD1 36 35 PTD0 34 33 ADP7 32 31 ADP6 30 29 ADP5 28 27 PTA2 26 25 PTA3 24 23 PTA4 22 21 PTG0 20 19 PTG1 18 17 PTE0 16 15 PTE1 14 13 PTE2 12 11 PTC6 10 9 PTC5 ...

Page 4

... C44 47μ 0.1μF C43 C41 0.1μF 0.1μF C39 C40 47μF 47μ C34 C35 2 2 0.1μF C32 47μ C31 5 J Sensors Freescale Semiconductor 0.1μF C46 21 29 Figure AN3956 4 ...

Page 5

... Screen 1: 1. Alti/Baro 2. Waterlevel 3. Inertial 4. Additional Screen 2: 1. Altimetry a. MPXM2102A b. MPL115A2 c. Experimental Sensors Freescale Semiconductor Information Displayed on LCD Push Buttons “Up, Down, ESC Enter” Blinking LEDs Figure 5. APEX Controls Press UporDN Press until option “1. Altimetry” is selected Press ENT ‘ ...

Page 6

... Screen 7: ALARM sounds when Threshold is reached Press. 97.273 kPa 97.836 ALARM Sensors Freescale Semiconductor Pressure and Temperature Raw Values in decimal 0367 format are on the right in blue. 0488 Press ENT menu Button one time to move forward to see the coefficients. 80 Coefficients are listed. Press ENT menu button to see 33 compensated pressure reading ...

Page 7

... Waterlevel Sensing 1. Alti/Baro Press 2. Waterlevel 2. Waterlevel UPorDN MPXV5004 Integrated 3. Inertial 40cm H2O Level 4. Additional ‘2’ ENT Sensors Freescale Semiconductor Press Please enter your UPorDN Altitude (m) UP/DN 00 ‘a’ 101.3 kPa ENT This is the altitude at your current location. Once its entered, the value of Pressure for that altitude is displayed ...

Page 8

... Waterlevel UPorDN MMA7361L 3 Axis 3. Inertial Accelerometer 1.5g 4. Additional ‘3’ ENT Sensors Freescale Semiconductor LARM sounds when Threshold is reached Press. 5.50 cm ALARM ENT Alarm is now Active. Note the outputs of the current Pressure in cm, and the Alarm Threshold point. Once crossed, the red LED will flash as the buzzer sounds ...

Page 9

... The values for the MPL115A are shown here. To the left are the Pressure and Temp ADC values in their raw form in HEX. To the right of them are the shifted values displayed in decimal. Sensors Freescale Semiconductor Press Raw Value Altitude UPorDN 0x017c1d 2(LP) value Pressure ‘ ...

Page 10

... MPXM2102A. The supply voltage is ratiometric, but at 10V supply, the FSS for 100 kPa of applied absolute pressure. The DEMOAPEXSENSOR does not have a full 10V supply. The part is biased instead supply. This cuts the FSS for 100 kPa. Since the output of an analog sensor is ratiometric to the input voltage crucial to have a stable supply voltage ...

Page 11

... This will reduce A/C and breeze effects on the pressure sensor. Most applications of such, include a housing perforated with small holes. This prevents a strong breeze from affecting the sensor, by filtering out the drastic pressure changes. DEMOAPEXSENSOR demo board, has no such housing. ...

Page 12

... For an 18-bit ADC conversion, 4.1V/262143 equals a resolution of 15.6 μV per a single ADC count. Since the differential span of the sensor is 1.62V after the amplifier, the span 100 kPa can be seen as a ADC value of 0 counts to 103846 counts. This makes each ADC count for the pressure span equivalent to 0.000963 kPa or 0.963 Pa. Sensors Freescale Semiconductor Table 3 h – ...

Page 13

... Reviewing Table 6, the DEMOAPEXSENSOR has code written to interpret small pressure changes and convert these to altitude. The conversion from pressure to altitude still has to use the exponential equation for a proper conversion. But the approximate distances and the ADC count equivalent are shown here. These are approximate across the pressure range but as written in the demo code, the pressure is determined first, the altitude second ...

Page 14

... A person sets a zero point before hiking a steep hill. At the top of the hill, the change in barometric pressure is related to meters or feet. This is a measure of the dynamic change of pressure over a short distance. This is a targeted application versus the other application of knowing the altitude from sea level at all times after one factory calibration. Sensors Freescale Semiconductor Calibration Section Calibration Section Difference in ...

Page 15

... The MPL115A is a small 1.2 mm digital absolute pressure sensor available in either I pressure range 115 kPa. This narrower range is more application specific for events occurring in that altitude or in devices requiring that pressure. In this section, the DEMOAPEXSENSOR’s implementation of the MPL115A and the information displayed on the APEX is described. ...

Page 16

... LEDs will light up green. After the alarm threshold is reached, the red LED toggles on/off while a buzzer is sounded. This can be activated via waiting for a pressure change, or applying pressure to the DEMOAPEXSENSOR. A clear Ziploc bag or syringe with a soft applicator tip useful in activating the alarm. ...

Page 17

... Waterlevel Implementation with the MPXV5004G The DEMOAPEXSENSOR has the MPXV5004G gauge pressure sensor on board. This is located on the backside of the demo board. It has a top port, which used with the supplied high temp silicone hose. The output of the MPXV5004G is shown in Table 9. Operating Characteristics (V ...

Page 18

... The best calibration would be a two part calibration. A Pressure would be taken The difference in ADC counts divided will give the number of ADC counts per a cm etc. for each sensor. 2 This is the best calibration, but is not implemented on the DEMOAPEXSENSOR in software rev 1.0. Sensors Freescale Semiconductor First Point: 0 Level, Water Surface Second Point: Bottom of Container Figure 11 ...

Page 19

... MMA7361L as the 0g-Detect pin. ‘1’ or logic high is the output for a detected Freefall. Note that this is also for Freefall in a linear fashion such that the board is not spinning or in rotation as it falls. The DEMOAPEXSENSOR emits a buzzer noise and a flashing red LED as the Freefall detect occurs. ...

Page 20

... Freescale Semiconductor product could create a situation where personal injury or death may occur. Should Buyer ...

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