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Load Cell Interfacing

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ex4

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I'm having difficulties interfacing load cell with 2mV/V fidelity :(
Can anybody suggest me how am i supposed to interface the small amount of electric changes of the load cell into some voltage that my AVR ATMEGA8535 can read? From what i've search from the net, 2mV/V fidelity gives you 10mV output on full load capacity with 5V voltage source (my load cell max load is 200kg)
I'm thinking using opamp OP07. Is that enough?
 

IanP

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For this application single opamp may be not enough ..
Much better results you can achieve by using instrumentation amplifier, which basically consists of at least 3 good quality opamps connected in a very specific configuration .. see picture below ..
If you need more hints on instrumentation amplifiers, have a look at:
http://www.ednasia.com/article.asp?articleid=4521
"The right way to use instrumentation amplifiers"

Regards,
IanP
 

ex4

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Well, that fix all of my problems :) :) :)
I've download their PDF files, and give a lot of information for my projects
My four thumbs are all for you :)
 

ifithegr8

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i have unknown full scale load cell will the above mentioned ckt will provide me full scale reading of 5 V at vout
 

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