Adaptive double recycling folded cascode amplifier

A new structure for improving the performance of recycling folded cascode (RFC) operational transconductance amplifier (OTA) is presented. The improvement has been achieved using two current recycling stages. The first current recycled stage acts as an adaptive biasing current source for the second stage. Compared to the RFC OTA, the proposed OTA shows a significant improvement in slew rate (SR), gain-band-width (GBW), and DC gain. Simulation results in 0.18 mu m standard CMOS technology exhibit that the proposed OTA achieves an about three times improvement in SR, 12.4 dB DC gain enhancement, and approximately two times increase in gain bandwidth compared to the RFC OTA. The proposed OTA consumes 433 mu W @1.8 V which makes it appropriate for low-power applications.