Voltage Amplifier Project

[mikaelsavage]

Hi, I have a project for a class I am working on where I have to use a strain guage to measure mass. I was able to setup a circuit that gave me a voltage return, but it only varies by 0.01 volts when the guage is bent. How would I go about amplifying this to get a greater varyiation. Also, I am not allowed to use preassembled devices or daughterboards, only simple components and dip's. Any help would be appreciated.

Thanks,
Mike

[LarryD]

We obviously need a lot more information from you.

Always show us a good schematic of your proposed circuit.
Show us a good image of your ‘actual’ wiring.
Give links to components.

Google instrumentation amplifier.

[jremington]

Use an instrumentation amplifier, like the INA121 or newer.

[build_1971]

If it is for a school project you might get away with an ordinary opamp. A factor 100 amplification should not be a problem...

[raschemmel]

LT1215 Difference Amplifier circuit
(see schematic on page 1)

[johnerrington]

Something like this:

Using Operational Amplifiers in your Arduino project

8: Example 2. Amplifying a signal from a sensor when it has an offset voltage Many common sensors will produce a voltage that does not "sit" on the 0V rail, as shown in the blue line in this example. [opamp signals3.png] The green signal is too small (say 0.04V) to measure with any accuracy; however by amplifying it by 100 we get a signal of around 0.04*100 = 4V that can be measured. However the signal on the blue line is small, but has a dc offset of about 2.5V; multipling that by 100 gives…