A QFGMOS-Based gm-Boosted and Adaptively Biased Two-Stage Amplifier Offering Very High Gain and High Bandwidth.

A low voltage low power two-stage CMOS amplifier with high open-loop gain, high gain bandwidth product (GBW) and enhanced slew rate is presented in this work. The proposed circuit makes use of folded cascode gm-boosting cells in conjunction with a low voltage gain enhanced cascode mirror using quasi-floating gate (QFGMOS) transistors. QFGMOS transistors are also used in input pair and adaptive biasing, which facilitate large dynamic output current in the presented circuit. Consequently, the slew rate is enhanced without much increase in static power dissipation. The unity gain frequency (UGF) and dc gain of the circuit are 29.4 MHz and 132 dB, respectively. The amplifier is operated at 0.6 V dual supply with 89 μ W power consumption and has a nearly symmetrical average slew rate of 51.5 V/ μ s. All simulations including Monte Carlo and corner analysis are carried out using 180-nm CMOS technology for validating the design with help of spice tools. [ABSTRACT FROM AUTHOR]