SaM ~ CMRR of a Simple Differential Amplifier

CMRR defintion: $CMRR = \frac{∣ A _{d} ∣}{∣ A _{C} ∣} = \frac{A _{2} - A _{1}}{2 ( A _{1} + A _{2} )}$
Circuit definition:
Find $A_{1}$ (inverting amplifier): $A_{1} = \frac{V _{0}}{V _{1}}_{V_{2} = 0} = - \frac{R _{2}}{R _{1}}$
Find $A_{2}$ (non-inverting amplifier): $A_{2} = \frac{V _{0}}{V _{2}}_{V_{1} = 0} = \frac{R _{4}}{R _{3} + R _{4}} \cdot (1 + \frac{R _{2}}{R _{1}})$
Calculate $A_{d}$ and $A_{c}$ : $A_{d} = \frac{1}{2} (\frac{R _{4} ( R _{2} + R _{1} )}{( R _{3} + R _{4} ) R _{1}} + \frac{R _{2}}{R _{1}}) A_{c} = \frac{R _{4} ( R _{2} + R _{1} )}{( R _{3} + R _{4} ) R _{1}} - \frac{R _{2}}{R _{1}}$
Calculate the CMRR: $CMRR = \frac{∣ A _{d} ∣}{∣ A _{C} ∣} = \frac{1}{2} \frac{\frac{R _{4} ( R _{2} + R _{1} )}{( R _{3} + R _{4} ) R _{1}} + \frac{R _{2}}{R _{1}}}{\frac{R _{4} ( R _{2} + R _{1} )}{( R _{3} + R _{4} ) R _{1}} - \frac{R _{2}}{R _{1}}}$

🪴 Quartz 4.0