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-1-V singlestage operational amplifiers have been designed and simulated in 0.18-mu m CMOS technology that confirm the suitable operation of the circuit in very-low supply voltages and different speeds.