DTMOS-Based Low-Voltage and Low-Power Two-Stage OTA

A dynamic threshold MOS (DTMOS) based operational transconductance amplifier (OTA) with low supply voltage and low power consumption is proposed in this paper. A two-stage structure is used to achieve higher voltage gain. The proposed OTA for eliminating common-mode signals and fixing the common-mode output voltage has a feedforward and feedback paths on the first and second stage, respectively. This OTA is designed and simulated with TSMC 0.18µm CMOS technology. The operating voltage of this circuit is 0.8 V and its DC gain is 75.31 dB. The unity gain frequency (UGF) and the phase margin of this OTA are 8.40 MHz and 54°, respectively. The power consumption of the proposed OTA with a 13 pF and 100 kΩ loads at output nodes is equal to 160 µW. Based on simulation results, using the proposed DTMOS-based OTA in low voltage and low power applications is a very good option.

Dynamic threshold MOS (DTMOS), Low-voltage and low-power, Operational Transconductance Amplifier (OTA), Two-stage structure