Domestic Indirect Feedback Compensation of multiple-stage amplifiers for multiple-voltage level-converting amplification

This investigation presents a Domestic Indirect Feedback Compensation (DIFC) operational amplifier for systems with both low voltage and high voltage circuits. The DIFC operational amplifier is capable of converting a voltage signal from a low voltage circuit and amplifying it into a large voltage signal to drive high voltage load. Since the Metal-Insulator-Metal (MIM) capacitors are not designed for high voltage applications and the feed-forward compensation causes pole-zero doublet as a result from the deviation of high voltage transistor characteristics from shuttle to shuttle, the DIFC is performed only using low voltage circuits. In other words, the feedback by connecting the output node of the operational amplifier is avoided. The proposed design is carried out using the TSMC 0.25 μm 1-poly 3-metal BCD process.