Stability Analysis of Two-Stage OTA with Frequency Compensation

In this paper, the design implementation of a two-stage operational transconductance amplifier (OTA) using a passive frequency compensation technique is presented. It is based on the Miller and passive frequency compensation techniques. The use of these techniques achieves the high gain-bandwidth product without an increase in the overall power consumption. It produced a -21.17dB of gain margin with a phase margin of 77° at a 1.8V power supply voltage. A resistor-capacitor pair in feed-forward compensation is connected in the first stage and a Miller compensation capacitor is introduced in the second stage of the circuit. The proposed op-amp design results in 1205 MHz of gain-bandwidth product. It is observed that the presented circuit performs better as compared to existing designed circuits.