L8

20/08/26 Thu 7:59am

Instrumentation Amplifier

It converts change in physical quantity/parameter such as temperature, intensity of light, etc into proportional voltage.

$$I=\frac{V_{01}-V_{02}}{2R+R_{gain}}$$

also

$$I=\frac{V_1-V_2}{R_{gain}}$$

equating the two we get

$$\frac{V_{01}-V_{02}}{2R+R_{gain}}=\frac{V_1-V_2}{R_{gain}}$$ $$\boxed{V_{01}-V_{02}=(V_1-V_2)\left(\frac{2R}{R_{gain}}+1\right)}$$ $$V_0\propto (V_{02}-V_{01})$$ $$V_0=A(V_{01}-V_{02})$$ $$V_0=\frac{R_2}{R_1}(V_{02}-V_{01})$$ $$V_0=-\frac{R_2}{R_1}(V_{01}-V_{02})$$ $$V_0=-\frac{R_2}{R_1}((V_1-V_2)\left(\frac{2R}{R_{gain}}+1\right))$$ $$\boxed{V_0=\left(1+\frac{2R}{R_{gain}}\right)\times (V_2-V_1)}$$

ADC

$Resolution=\frac{V_{ref}}{2^n}$