Load Cell Interfacing

[ex4]

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]

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:
**broken link removed**
"The right way to use instrumentation amplifiers"

Regards,
IanP

 

[ex4]

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]

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