A strain gauge is a sensor whose resistance varies with applied force. To measure the variation in resistance, the strain gauge is placed in a bridge configuration. This design uses a 2 op amp instrumentation circuit to amplify a differential signal created by the change in resistance of a strain gauge. By varying R10, a small differential voltage is created at the output of the Wheatstone bridge which is fed to the 2 op amp instrumentation amplifier input.
- Single 5V supply with half-supply reference
- Input: -2.22mV to 2.27mV differential
- Output: 225mV - 4.72V
- Strain gauge resistance variation: 115 - 125 Ohms
- Gain: 1001V/V