diff --git a/uni/mmme/2051_electromechanical_devices/piezoelectrics.md b/uni/mmme/2051_electromechanical_devices/piezoelectrics.md index aa79a6e..aca7421 100755 --- a/uni/mmme/2051_electromechanical_devices/piezoelectrics.md +++ b/uni/mmme/2051_electromechanical_devices/piezoelectrics.md @@ -34,8 +34,8 @@ This is done using the following amplifier: ![](./images/vimscrot-2023-03-16T11:22:04,554599428+00:00.png) \begin{align*} -V_\text{out} &= A_{OL}(V^+-V__) = -A_{OL}V__ \\ -V__ &= V_\text{out} - V_C +V_\text{out} &= A_{OL}(V^+-V_{-}) = -A_{OL}V_{-} \\ +V_{-} &= V_\text{out} - V_C \end{align*} As input resistance of op amp is infinite: