1 motorola sensor device data prepared by: bill lucas and warren schultz a plugin module that is part of a systems development tool set for pressure sensors is presented here. it provides an analog signal from an MPX5000 series sensor to a motorola sensor development controller, or can be used stand alone to provide power and signal connections to the sensor. plugin module description a summary of information for using systems development plugin module asb205 includes the schematic in figure 2, connector pinout in figure 3, a pin by pin description of functionality, specs in tables 13, and a parts list in table 4. figure 4 in the applications section provides a quick reference for making connections. a discussion of the design appears under the heading design considerations. function the plugin module shown in figure 1 is designed to supply pressure and temperature inputs to a sensor development controller. the sensor output is filtered and buffered with a unity gain rail to rail amplifier. if desired, jumpers on the board allow direct connection of the sensor output to the controller. connections are made through a db9 connector, which allows this board to be plugged directly into its controller. if physical separation is desired, a standard 9 wire straightthrough serial cable can be inserted between the two boards. alternately, connections for 5 volts, ground, and the output signal can be made through screw terminals at the top of the board. a socket for sensor connections makes changing from one pressure range to another relatively easy. figure 1. asb205 e MPX5000 series sensor module order this document by an1653/d
semiconductor application note ? motorola, inc. 1998 rev 1
2 motorola sensor device data figure 2. schematic r5 300 r3 300 d1 d2 2 1 2 1 +5 range rt1 10 k c2 0.01 f tp2 r4 10 k 1% 5 9 4 8 3 7 2 6 1 + + tp1 db9 p1 r2 750 rg open 5 6 7 u2b mc33202 3 2 1 u2a mc33202 gnd gnd 3 1 2 b+ u1 mpx5010 kgnd cntl vs1 gnd +5 nc jt6 jt5 jt4 jt3 jt2 jt1 vs2 c1 tp3 out c3 0.33 f j2 j1 r1 750 r6 47 k 0.33 f j3 j4 vs1 electrical characteristics the electrical characteristics in tables 1, 2, & 3, apply to operation at 25 degrees celsius, and unless otherwise specified a +5 volt input of 5.00 volts. the values in tables 2 and 3 are nominal values. table 1. electrical characteristics characteristic symbol min typ max units dc supply voltage +5 4.75 5.0 5.25 volts pressure sensor output voltage e zero pressure e full scale vs1 e e e e 200 4.7 e e mv volts temp sensor output voltage vs2 e 2.5 e volts quiescent current i cc e 25 e ma
3 motorola sensor device data table 2. output characteristics (vs1) sensor full scale pressure (kpa) sensitivity (mv/kpa) zero pressure offset (volts) full scale output voltage (volts) full scale span (volts) mpx5006* 6 750 .2 4.7 4.5 mpx5010* 10 450 .2 4.7 4.5 mpx5050 50 90 .2 4.7 4.5 mpx5100* 100 45 .2 4.7 4.5 mpx5700* 700 6.43 .2 4.7 4.5 mpx5999 1000 4.5 .2 4.7 4.5 *included with asb205 kit table 3. vs2 versus temperature temperature c r t ohms vs2 volts temperature c r t ohms vs2 volts 0 32773 1.17 40 5323 3.26 5 25456 1.41 45 4365 3.48 10 19932 1.67 50 3599 3.68 15 15725 1.94 55 2983 3.85 20 12497 2.22 60 2486 4.00 25 10000 2.50 65 2082 4.14 30 8055 2.77 70 1753 4.25 35 6528 3.03 75 1482 4.35 content board contents are described by the following parts list and the schematic in figure 2. a pin by pin circuit description follows in the next section. table 4. parts list item quantity reference part 1 2 c1,c3 .33 m f ceramic 2 1 c2 .01 m f ceramic 3 2 d1 led (red) 4 1 d2 led (red) 5 4 tp1,tp2,tp3,gnd test point 6 6 jt1jt6 screw terminal 7 2 j1,j2 jumperwire 8 1 p1 db9 connector 9 2 rt1 10k thermistor 10 1 r4 10k 1% 11 2 r2,r1 750 12 2 r5,r3 300 13 1 r6 47k 14 1 u1 mpx5010 15 1 u2 mc33202 pin by pin description inputs and outputs are grouped into two connectors. a db9 connector provides a plugin feature. if this connector is used, no other connections are necessary. alternately, power, ground, and sensor output connections can be made through screw terminals at the top of the board. the screw terminals and the db9 are wired in parallel. db9 connector pinouts are shown in figure 3. 5 9 4 8 3 7 2 6 1 cntl gnd open kgnd gnd vs1 vs2 +5 open figure 3. db9 pinout db9 connector +5: 5 volt power is supplied through pin 5 on the db9 connector. gnd: the ground connection is on pin one. it connects the sensor's analog ground to the controller's digital ground. kgnd: an additional ground connection, labeled kgnd, is made on pin 2. as shipped, kgnd is tied to gnd via jumper j1. if j1 is opened, kgnd provides a separate return for the temperature sensor. this feature can be helpful if a cable is used between the sensor module and its controller.
4 motorola sensor device data vs1: the pressure sensor output signal, vs1, is on pin 3. this is the sensor's output, filtered and then buffered with a unity gain amplifier. if direct connection to the sensor's output is preferred, it will appear on this pin when jumper j2 is open, and a wire is soldered into jumper j3. vs2: a temperature dependent output signal is supplied on pin 4. it is supplied from a thermistor that has a nominal output voltage of 2.5 volts at 25 degrees c. this thermistor sees a temperature rise due to power dissipation on the board, and typically reads several degrees higher than ambient in still air. cntl : a control signal is supplied on pin 6. it is normally high, and switches low to light the range light when the sensor's full scale pressure is exceeded. with code modifications, the pressure at which this transition occurs can be changed, and the signal used to control an external device. board code: a board code that lets the controller know that this is an MPX5000 series module is supplied with a ground on pin 8 and an open on pin 7. pin 9: there is no connection made to pin 9 on this board. however, power supply voltage b + will be present on this pin when plugged into a motorola sensor development controller. screw terminals connections for +5, vs1, cntl, kgnd , & gnd are wired in parallel with the db9 connector. as shipped, kgnd and gnd are tied together with jumper j1. a no connect terminal labeled, nc, is tied to jumper j4 which is open. if a wire is placed in j4, this terminal is then connected to the sensor output. test points tp1tp3, & gnd test points tp1, tp2, & tp3 provide access to output signals. tp1 is connected to the filtered and buffered pressure sensor output signal. tp2 is connected to the thermistor output signal, and tp3 is connected to sensor's output. a test point for ground is also provided. indicator lights +5: the +5 light is provided to indicate the presence of 5 volt power. range: the range indicator light turns on when the sensor's full scale pressure range is exceeded. application example an application example shown in figure 4 illustrates system connections to an asb200 control board and a pressure source. this arrangement can be run stand alone, or the asb200 can be connected to an mmds or mmevs system for code development. the two boards are designed such that the db9 connectors plug into each other. once they are plugged in it is only a matter of connecting a power supply and a pressure source to get a system up and running. if physical separation between the sensor location and the controller is desired, a standard 9 wire straightthrough serial cable can be used between the two boards. measuring different pressure ranges is facilitated by using a socket for the sensor that is supplied on the board. pads for an mpx5006 are also provided. to use the mpx5006, it is necessary to have the 6 pin socket empty, snap in the mpx5006, and then solder its leads to the pads that are provided. the correct orientation is with its marking facing the front of the board. sensor development controller motorola asb200 kgnd gnd +5 vs1 vs2 gnd b+ nc +5 vs1 cntl kgnd gnd motorola asb205 7.526 vdc lcd figure 4. application example pressure (top port) or vacuum* (bottom port) *vacuum port is not available on mpx5006
5 motorola sensor device data design considerations MPX5000 sensors are plug and play devices in most applications, particularly when connected to a microcontroller with an 8 bit a/d converter. although micro's with 8bit a/d's are most common, higher resolution a/d's, such as the one on the 68hc705jp7 in this tool set, are becoming increasingly popular. with these higher resolution a/d's, the noise that is inherent to piezoresistive bridges becomes a design consideration. for that reason, the sensor's output is filtered with a single pole filter, and then buffered with a unity gain buffer. an mc33202 rail to rail operational amplifier was chosen for its ability to drive cable capacitance, in the event that a cable is used between the plugin module and controller. for applications where the sensor and microcontroller are on the same board, an mc33502 is a better choice, due to its lower offset voltage. conclusion the asb205 plugin module is part of a systems development tool set for pressure sensors. it provides pressure and temperature input signals to a motorola sensor development controller, or can be used stand alone to provide power and signal connections to MPX5000 series sensors.
6 motorola sensor device data notes
7 motorola sensor device data notes
8 motorola sensor device data motorola reserves the right to make changes without further notice to any products herein. motorola makes no warranty, represe ntation or guarantee regarding the suitability of its products for any particular purpose, nor does motorola assume any liability arising out of the applicati on or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. atypicalo para meters which may be provided in motorola data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. all ope rating parameters, including atypicalso must be validated for each customer application by customer's technical experts. motorola does not convey any license under it s patent rights nor the rights of others. motorola products are not designed, intended, or authorized for use as components in systems intended for surgical imp lant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the motorola product cou ld create a situation where personal injury or death may occur. should buyer purchase or use motorola products for any such unintended or unauthorized application, buyer shall indemnify and hold motorola and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expens es, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized u se, even if such claim alleges that motorola was negligent regarding the design or manufacture of the part. motorola and are registered trademarks of motoro la, inc. motorola, inc. is an equal opportunity/affirmative action employer. mfax is a trademark of motorola, inc. how to reach us: usa / europe / locations not listed : motorola literature distribution; japan : nippon motorola ltd.; spd, strategic planning office, 141, p.o. box 5405, denver, colorado 80217. 13036752140 or 18004412447 4321 nishigotanda, shinagawaku, tokyo, japan. 813 54878488 customer focus center: 18005216274 mfax ? : rmfax0@email.sps.mot.com touchtone 1 6022446609 asia / pacific : motorola semiconductors h.k. ltd.; 8b tai ping industrial park, motorola fax back system us & canada only 18007741848 51 ting kok road, tai po, n.t., hong kong. 85226629298 http://sps.motorola.com/mfax/ home page : http://motorola.com/sps/ an1653/d ?
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