Positive feedback technique for DC-gain enhancement of folded cascode Op-Amps

In this paper, a novel folded cascode operational amplifier is proposed which improves DC-gain using positive feedback technique. This method does not affect the unity-gain frequency, stability, power dissipation, and output voltage swing of the conventional folded cascode Op-Amp. The proposed Op-Amp was designed in a standard 0.18μm TSMC 1.8V CMOS technology. Simulation results show a DC-gain enhancement of 25dB and 513MHz unity gain bandwidth for the presented Op-Amp. HSPICE simulation results confirm the theoretical estimated improvements.