A 0.3V Rail-to-Rail Three-Stage OTA With High DC Gain and Improved Robustness to PVT Variations

This paper presents a novel 0.3V rail-to-rail body-driven three-stage operational transconductance amplifier (OTA). The proposed OTA architecture allows achieving high DC gain in spite of the bulk-driven input. is due to doubled body at first and third stages, gain, gate-driven second stage. bias current each branch accurately set through or mirrors, thus guaranteeing an outstanding stability main performance parameters PVT variations. In stage, input signals drive bulk terminals both NMOS PMOS transistors complementary fashion, allowing common mode range (ICMR). stage gate-driven, pseudo-differential with local CMFB. implements differential-to-single-ended conversion pair mirror. Thanks adoption two fully differential stages feedback (CMFB) loop, common-mode rejection ratio (CMRR) typical conditions greatly improved respect other ultra-low-voltage (ULV) OTAs. has been fabricated commercial 130nm CMOS process from STMicroelectronics. Its area about 0.002 mm 2 , power consumption less than 35nW supply-voltage 0.3V. With load capacitance 35pF, exhibits unity-gain frequency 85dB 10kHz, respectively.