Ultra-Low-Voltage, Low-Power, High-Speed Operational Amplifiers Using Body-Driven Gain-Boosting Technique

Regular gate-driven regulated-cascode structure fails to operate with very-low supply voltages. On the other hand, body-driven configuration suffers from limited speed due to limited effective transconductance. In this letter, body-driven gain-boosting amplifier has been employed for a regular gate-driven folded-cascode amplifier to enhance its voltage gain without any limitation on its minimum required supply voltage and voltage swing in ultra-low-voltage applications. The gain/speed/swing performance of the proposed low-voltage op-amp would be therefore good enough not to require another amplifying stage in many high-speed low-power applications. Using the proposed architecture, three different sub-l-V single-stage operational amplifiers have been designed and simulated in 0.18-mum CMOS technology that confirm the suitable operation of the circuit in very-low supply voltages and different speeds.