0.4-V, 81.3-nA Bulk-Driven Single-Stage CMOS OTA with Enhanced Transconductance

The paper describes a single-stage operational transconductance amplifier suitable for very-low-voltage operation in power-constrained applications. The proposed circuit avoids the tail current generator in the differential pair while preventing pseudo-differential operation. Moreover, the adoption of positive feedback allows increasing the stage transconductance while minimizing the current consumption. Experimental measurements on prototypes implemented in a standard CMOS 180-nm technology, show superior performance as compared to the state of the art.