A technique to enhance the transconductance of micro-power improved recycling folded cascode operational transconductance amplifier with reasonable phase margin

Abstract

To keep a pace with the modern digital circuits, a development of a high performance low voltage and low power analog circuits is one of the challenging tasks. This paper presents a low voltage low power advanced folded cascode operational transconductance amplifier (OTA) with an improved transconductance and DC gain. The proposed structure adopts a power efficient current recycling folded cascode structure with an asymmetrical current split input stage. To achieve a low voltage and low power operation, all the transistors are biased in a weak inversion region. The proposed structure shows a significant enhancement in transconductance outcomes in the increased DC gain and gain bandwidth product (GBW) with a comparative phase margin for the same value of a load capacitor in a low voltage environment. The proposed OTA is implemented in 0.18 um CMOS technology. It shows approximately 8.96° advancement in a phase margin and 2.76 dB hike in a DC gain with an equal GBW compared to its original OTA counterpart structure at 0.5 V supply voltage.