Non-inverting band-pass 1st order

Transfer function: $H(j\omega )=1+\frac{j\omega .R_2{C}_1}{(1+j\frac{\omega }{{\omega }_1})\left(1+j{\displaystyle \frac{\omega }{{\omega }_2}}\right)}$

If C₁ > 100*C₂: $H(j\omega )\simeq \frac{(1+j\frac{\omega }{{\omega }_0})\left(1+j\frac{\omega }{{\omega }_3}\right)}{(1+j\frac{\omega }{{\omega }_1})\left(1+j{\displaystyle \frac{\omega }{{\omega }_2}}\right)}$

With:

$f_0=\frac{1}{2\pi .(R_1+R_2)C_1}$

$f_1=\frac{1}{2\pi .R_1{C}_1}$

$f_2=\frac{1}{2\pi .R_2{C}_2}$

$f_3=\frac{1}{2\pi .(R_1\parallel R_2)C_2}$

Gain when ω < ω₀: $|H(j\omega )|\stackrel{\omega <{\omega }_0}{\to }1$

Gain in the bandwidth (ω₁ < ω < ω₂): $|H(j\omega )|\simeq \frac{{\omega }_1}{{\omega }_0}=1+\frac{R_2}{R_1}$

Gain when ω > ω₃: $|H(j\omega )|\stackrel{\omega >{\omega }_3}{\to }\frac{{\omega }_1.{\omega }_2}{{\omega }_0.{\omega }_3}=1$