The circuit has gain and phase Bode plots of the standard form in Fig. 1.23. As the gain falls off at the
rate of –20 dB/decade, it will reach 0 dB in two decades, that is, at f = 100f0 = 100 kHz. As Fig.
1.23(b) indicates, at such a frequency which is much greater than f0, the phase is approximately −90°.
To this, however, we must add the 180° arising from the inverting nature of the amplifier (i.e., the
negative sign in the transfer function expression). Thus at 100 kHz, the total phase shift will be −270°
or, equivalently, +90°.