For the circuit of the given figure with an ideal operational

For the circuit of the given figure with an ideal operational amplifier, maximum phase shift of the output V_out with reference to the input V_in is

From the circuit,

V₊ =	V_in
	1 + jωRC

and V_– =V₊ (Ideal OPAMP) Now

Now	V_in - V_–	=	V_– – V₀
	R₁		R₁

⇒ V₀ = 2V_– – V_in = 2V₊ – V_in

=		2	- 1		V_in =	1 - jωRC	V₀
		1 + jωRC				1 + jωRC

∴ ∠ (V₀ / V_i) = - 2 tan^-1 ωRC
For – 90 ≤ θ ≤ 90°
Phase-shift ∠ (V₀ / V_i) = ± 180°