PROJECT TITLE :

A Highly Efficient Composite Class-AB–AB Miller Op-Amp With High Gain and Stable From 15 pF Up To Very Large Capacitive Loads - 2018

ABSTRACT:

In this paper, a highly power-economical category-AB–AB Miller op-amp is discussed. The structure uses gmenhancement primarily based on native common-mode feedback to supply class-AB operation with enhanced effective gm , open-loop gain, unity-gain frequency, and slew rate ( SR ) while not significant increase in quiescent power consumption. Utilization of a nonlinear load leads to large symmetric positive and negative SRs . Stability over an extremely wide selection of capacitive hundreds is achieved through a mixture of Miller and section-lead compensations. The unity-gain frequency will not show sensitivity to capacitive load values. A test chip prototype fabricated in zero.eighteen- µm CMOS technology shows ninety.eight-dB open-loop gain, twelve.five-MHz bandwidth for a 25-pF load capacitance, and a factor 60 SR enhancement with most output current close to 1-mA and forty three- µA total static current.