AN4007 D

The Datasheet King - 100 Million Datasheets from 7500 Manufacturers.

Datasheet Thumbnail

Top Searches for this datasheet

vacuum tube 80 - vacuum tube 80
vacuum cylinder - vacuum cylinder
surface mount pressure sensor - surface mount pressure sensor
STRAIN GAUGE motorola - STRAIN GAUGE motorola
pressure sensor signal conditioning - pressure sensor signal conditioning
pressure sensor devices - pressure sensor devices
pressure reducing valve - pressure reducing valve
piezoresistive pressure sensor medical - piezoresistive pressure sensor medical
negative PRESSURE SENSOR - negative PRESSURE SENSOR
MEDICAL PRESSURE SENSOR - MEDICAL PRESSURE SENSOR
high pressure sensor circuit - high pressure sensor circuit
harsh environment PRESSURE die - harsh environment PRESSURE die
gasoline direct injection - gasoline direct injection
ESP car - ESP car
diaphragm pressure sensor - diaphragm pressure sensor
control valve air pump - control valve air pump
Automotive motorola - Automotive motorola
application notes pressure sensor signal conditio - application notes pressure sensor signal conditio
analog pressure sensor vacuum - analog pressure sensor vacuum
analog pressure sensor - analog pressure sensor
air pressure sensor tube - air pressure sensor tube
"vacuum sensor" - "vacuum sensor"
AN4007 - AN4007

SEMICONDUCTOR APPLICATION NOTE
Order this document AN4007/D
Small Amplified Automotive Vacuum Sensors Single Chip Sensor Solution Brake Booster Monitoring
Prepared Marc Osajda Automotive Sensors Marketing Sensor Products Division Motorola Semiconductors S.A. Toulouse France
AN4007
BRAKING SYSTEMS
Different types braking principles found vehicles depending whether brake system only activated muscular energy power assisted (partially completely). Muscular activated brakes mostly found motorcycles very light vehicles. driver's effort hand lever pedal directly transmitted hydraulic link brake pads. Power assisted brakes found most passenger cars some light vehicle trucks. this case, driver's effort amplified brake booster increase force applied brake pedal.
BRAKE BOOSTER OPERATION PRINCIPLE
vacuum brake booster system using differential between atmospheric pressure lower pressure source (vacuum) assist braking operation. brake booster located between brake pedal master cylinder. Figure shows simplified schematic vacuum brake booster. When brake pressure applied push (brake pedal side), intake valve closed vacuum valve open. Thus, both vacuum working chambers same pressure, typically around below atmospheric pressure). Vacuum generated either engine intake manifold auxiliary vacuum pump.
RUBBER MEMBRANE PISTION
CONNECTION VACUUM PUMP ENGINE INTAKE MANIFOLD PUSH MASTER CYLINDER
PUSH FROM BRAKE PEDAL
INTAKE VALVE VACUUM VALVE
VACUUM CHAMBER
WORKING CHAMBER
Figure Brake Booster Simplified Schematic
Motorola Sensor Device Data Motorola, Inc. 2000
AN4007
Once brake pedal activated (force Fp), vacuum valve closed intake valve open proportionally displacement push (Figure working chamber progressively open atmospheric pressure, which creates differential between vacuum chamber working chamber. This differential pressure applied surface piston results force forces then applied brake pads through master cylinder hydraulic links. When brake pedal released, spring moves piston back, closing intake valve opening vacuum valve rebalance pressure between chambers.
Figure Braking Phase
VACUUM GENERATION
most passenger cars, vacuum generated engine itself. When engine throttle valve closed, displacement pistons produces vacuum intake manifold. Thanks tube hose connected between engine intake manifold brake booster, vacuum applied chambers. backslash valve inserted between intake manifold booster maintains vacuum booster when engine throttle valve open.
INTERFACE PUMP CONTROL CIRCUIT
This principle some limitations, however. example, only used engines that have ability generate enough vacuum. diesel engines, which have throttle valve, necessary auxiliary pump generate vacuum. This will also case Gasoline Direct Injection (GDI) engine, where some driving conditions (idle, lean burn) electrically assisted throttle valve will maintained slightly open. this situation, vacuum available intake manifold sufficient provide efficient braking.
PRESSURE SENSOR
VACUUM FEEDBACK ELECTRICAL VACUUM PUMP
VACUUM GENERATION
Figure Vacuum Pump Monitoring Therefore, necessary desirable electrical pump that will generate vacuum brake booster. auxiliary electrical pump (Figure provides several advantages over "intake manifold" vacuum. Vacuum generation longer related engine running condition. Vacuum only generated controlled pump thanks vacuum pressure sensor that provides accurate reading pump electrical control circuit. electrical pump switched based required vacuum. compensate atmospheric pressure variation order maintain constant booster effect, pump also switched independently from atmospheric pressure. Various algorithms driving pump implemented depending required braking conditions. Pressure variations during braking measured, pump activated generated additional vacuum required increase braking force. Leakage detected pressure sensors pump switched compensate them. driver informed type failure thanks interface. Vacuum level, thus available braking force communicated through other braking systems such example, ESP. Motorola, worldwide leader automotive semiconductors, introduced integrate pressure sensor dedicated vacuum measurements applications such brake booster monitoring. single-chip vacuum sensor placed directly onto pump electronic control unit integrated component within brake booster, thus providing flexibility, system integration reduced system cost.
Motorola Sensor Device Data
AN4007
Motorola's MPXV4115V Vacuum Sensor
PIEZORESISTIVE/AMPLIFIED SENSORS
Motorola's pressure sensors based piezoresistive technology that consists silicon micromachined diaphragm diffused piezoresistive strain gauge. When vacuum pressure applied die, diaphragm deformed stressed. resulting constraints create variation resistance piezoresistive strain gauge. order read this variation, excitation current passes through gauge, voltage proportional applied pressure excitation current appears between voltage taps. accurate pressure reading, such sensing element needs usually calibrated, temperature compensated amplified. order solve inherent limitation basic sensing element, Motorola produces entire family calibrated, thermally compensated amplified pressure sensors (Figure called Integrated Pressure Sensors (IPS). state art, monolithic, amplified signal-conditioned silicon pressure sensor. sensor combines advanced micromachining techniques, thin film memorization bipolar semiconductor processing provide accurate, high-level analog output that proportional applied pressure. sensors directly connected converter.
SENSING ELEMENT
THERMAL COMPENSATION
AMPLIFIER
Figure Integrated Pressure Sensor Block Diagram
PRESSURE MEASUREMENT CONVENTION
Pressure measurements divided into three different categories: absolute, gage differential pressure. Absolute pressure refers absolute value force unit area exerted surface fluid. Therefore, absolute pressure difference between pressure given point fluid absolute zero pressure perfect vacuum. Gage pressure measurement difference between absolute pressure local atmospheric pressure. Local atmospheric pressure vary depending ambient temperature, altitude local weather conditions.
standard atmospheric pressure level 20_C 101.325 absolute. When referring pressure measurement, critical specify what reference pressure related gage absolute. gage pressure convention always positive. `negative' gage pressure defined vacuum. Figure shows relationship between absolute, gage pressure vacuum. Differential pressure simply measurement unknown pressure with reference another unknown pressure. pressure measured difference between unknown pressures. Since differential pressure measure pressure referenced another, necessary specify pressure reference.
GAGE
LOCAL ATMOSPHERIC PRESSURE
ABSOLUTE ATMOSPHERIC
VACUUM
ABSOLUTE
Figure Pressure Convention
Motorola Sensor Device Data
AN4007
TRANSFER FUNCTION
behavior defined linear transfer function. This transfer function applies Motorola's Integrated Pressure Sensors whatever pressure range type sensing element (absolute differential). variables dependent user application must remain within operating specification device.
MPXV4115V INTEGRATED PRESSURE SENSOR
Motorola MPXV4115V gauge vacuum sensor, designed measure pressure below atmospheric pressure, suitable automotive application such vacuum pump brake booster monitoring. MXPV4115V also ideal non-automotive applications where vacuum control required. MPXV4115V following basic characteristics (Note: Detailed characteristics Motorola's pressure sensors found
Vout Sensor output voltage Applied pressure Sensor supply voltage Sensitivity constant V/V/kPa Offset Constant inV/V Pressure error Temperature multiplier constants, specific each device, temperature pressure encountered application.
MPXV4115V CHARACTERISTICS
0.007652
0.92)
0.007652)
TYPICAL VOLTS TRANSFER FUNCTION: Vout 2.30 Vout ([0.007652 0.92)
VACUUM
-120
-100
REFERENCE: ATMOSPHERIC PRESSURE
VACUUM (below atmospheric pressure)
Figure MPXV4115V Transfer Function applied vacuum sensor pressure port. Pressures below atmospheric pressure have negative sign. example, below atmospheric transfer function. pressure higher than atmospheric pressure, device will electrically saturate. sensor designed measure vacuum from (Atmospheric pressure applied sensor pressure port) down 115kPa. Since MPXV4115V using atmospheric pressure reference, -115 only reached atmospheric pressure higher equal than kPa. device will electrically saturate vacuum below -115 kPa. 1.725 (1.5% full scale span) over entire pressure range between +85_C, -40_C +125_C. linear response from -40_ from 125_C. real intent pressure-sensor user know measured pressure. this case preferable express transfer function
(Vout 0.92) 0.007652
example, Vout 2.30 power supply 25_C ambient temperature, measured vacuum -60.1 1.725 kPa.
Motorola Sensor Device Data
AN4007
SENSOR PACKAGING
packaging pressure sensor critical achieve optimal performances final product. package must isolate pressure sensor from unwanted external stress which cause undesired drift electrical signal while being robust enough support pressure applied device without cracks, leaks mechanical failures. must media compatible same reasons.
APPLIED PRESSURE VACUUM) FLAT RING
CUSTOMER PRESSURE PORT APPLICATION HOUSING
PACKAGE CASE
PRINTED CIRCUIT BOARD SNAP-FIT
SCREW
small pressure sensor package from Motorola addresses those requirements lets designers mount pressure sensor directly printed circuit board, thus providing great flexibility space saving design. Figure shows typical assembly using small outline package (SOP) Case 482-01. sensor mounted printed circuit board automatic pick place machine with every other surface mount component. Sealing done using silicone flat ring inserted application housing. printed circuit board must maintained against flat ring either snap fit, screws shown. small outline package (SOP) fabricated using poly-phenyl sulfide (PPS), robust material, which withstand high temperatures highly resistant chemicals. Consequently, package ideal harsh environment such automotive, industrial medical systems. small outline package suitable Motorola's sensor chips from basic uncompensated sensor fully integrated sensing solution that include amplifiers other circuitry chip. Motorola's sensors using this package available both tubes tape reel configuration high productivity your assembly line.
Figure Mounting Suggestion
Motorola Sensor Device Data
AN4007
NOTES
Motorola Sensor Device Data
AN4007
NOTES
Motorola Sensor Device Data
AN4007
Mfax trademark Motorola, Inc.
Motorola reserves right make changes without further notice products herein. Motorola makes warranty, representation guarantee regarding suitability products particular purpose, does Motorola assume liability arising application product circuit, specifically disclaims liability, including without limitation consequential incidental damages. "Typical" parameters which provided Motorola data sheets and/or specifications vary different applications actual performance vary over time. operating parameters, including "Typicals" must validated each customer application customer's technical experts. Motorola does convey license under patent rights rights others. Motorola products designed, intended, authorized components systems intended surgical implant into body, other applications intended support sustain life, other application which failure Motorola product could create situation where personal injury death occur. Should Buyer purchase Motorola products such unintended unauthorized application, Buyer shall indemnify hold Motorola officers, employees, subsidiaries, affiliates, distributors harmless against claims, costs, damages, expenses, reasonable attorney fees arising directly indirectly, claim personal injury death associated with such unintended unauthorized use, even such claim alleges that Motorola negligent regarding design manufacture part. Motorola registered trademarks Motorola, Inc. Motorola, Inc. Equal Opportunity/Affirmative Action Employer.
reach USA/EUROPE/Locations Listed: Motorola Literature Distribution; P.O. 5405, Denver, Colorado 80217. 1-303-675-2140 1-800-441-2447 JAPAN: Motorola Japan Ltd.; SPS, Technical Information Center, 3-20-1, Minami-Azabu. Minato-ku, Tokyo 106-8573 Japan. 81-3-3440-3569 ASIA/PACIFIC: Motorola Semiconductors H.K. Ltd.; Silicon Harbour Centre, King Street, Industrial Estate, N.T., Hong Kong. 852-26668334 Customer Focus Center: 1-800-521-6274 MfaxTM: RMFAX0@email.sps.mot.com TOUCHTONE 1-602-244-6609 Motorola Back System Canada ONLY 1-800-774-1848 http://sps.motorola.com/mfax/ HOME PAGE: http://motorola.com/sps/
Motorola Sensor Device Data
AN4007/D

AN4007 D

Top Searches for this datasheet

Other recent searches