A high gain operational amplifier via an efficient conductance cancellation technique

An efficient conductance cancellation method is introduced to achieve high gain operational amplifiers. Without the aid of any tuning circuit, in IBM 130nm CMOS process, the post-layout simulation results show that proposed method is able to maintain a DC gain boost of over 23.2dB under temperatures between -40°C and 80°C, of over 21.1dB under supply voltage between 1.3V and 1.8V, and of over 22.5dB under output voltage swing between 0.1V and 1.3V. The measurement results show that the proposed technique maintains at least 26.4dB DC gain enhancement under output voltage swing between 0.1V and 1.4V, while the power consumption and area overhead of the proposed circuit are respectively less than 2% and 3% of those of the conventional op amps.