Active-Feedback Single Miller capacitor Frequency Compensation Techniques for Three-Stage amplifiers

This paper presents two novel active-feedback single Miller capacitor frequency compensation techniques for low-power three-stage ampli ̄ers. These techniques include the active-feedback single Miller capacitor frequency compensation (AFSMC) and the dual active-feedback single Miller capacitor frequency compensation (DAFSMC). In the proposed techniques, only one Miller capacitor in series with a current bu®er is utilized. The main advantages of the proposed three-stage ampli ̄ers are the enhanced unity-gain bandwidth and the reduced silicon area. Small-signal analyses are performed and the design equations are obtained. Extensive HSPICE simulation results are provided to show the usefulness of the proposed AFSMC and DAFSMC ampli ̄ers in both large and small capacitive loads.