Improved synthesis of gain-boosted regulated-cascode CMOS stages using symbolic analysis and gm/ID methodology

A systematic study of the gain-boosted regulated-cascode operational transconductance amplifier (OTA) CMOS stage is presented. Symbolic analysis is used first to describe the pole-zero behaviour and second to propose design criteria for optimal settling time. A synthesis procedure based on the “gm/ID” methodology is considered further on for quick optimization of the architecture based on the dc open-loop gain, transition frequency, and settling time specifications. Practical design cases are finally discussed.