High-efficiency 0.3V OTA in CMOS 130nm technology using current mirrors with gain

This paper presents a novel ultra-low-power ultra-low-voltage operational transconductance amplifier (OTA). The OTA operates with a 0.3V supply voltage and shows remarkable bandwidth performance with very limited power consumption, owing to the use of current mirrors with gain. Low impedance internal nodes of the current mirrors allow to boost gain and bandwidth, adding only high-frequency poles to the frequency response. Therefore, the compensation of the proposed OTA can be achieved through a dominant pole at the output, as in conventional cascode amplifiers. The circuit employs two identical input stages with cross-coupled inputs to improve common-mode rejection ratio (CMRR) performance, and a differential-to-single-ended output stage. The resulting architecture achieves a remarkable FOMS value, as demonstrated by the simulations performed in a commercial 130nm CMOS technology.