A Simple Miller Compensation With Essential Bandwidth Improvement

A novel technique for adaptive frequency compensation in negative feedback amplifiers is proposed. It is demonstrated that a simple reconnection of the compensation capacitor in a two-stage Miller op-amp leads to a pseudoconstant bandwidth for a moderate range of closed-loop gains, without requiring additional power dissipation or extra silicon area. Also, an improvement of power-supply rejection ratio is obtained. The presented technique has been applied to a non-inverting amplifier, which has been fabricated in a 0.18-μm CMOS process. Measurement results validating the proposed compensation scheme are provided.