A NEW TWO-STAGE OP-AMP USING GAIN-BOOSTED AND POSITIVE FEEDBACK TECHNIQUS

Operational amplifiers (OP-AMP) are the most important and most usable parts of analog and hybrid circuits (digital-analog). In the field of integrated circuits, the use of an element that has the best efficiency in designing of amplifiers; because play an important role and echnology realization and its creation is a necessity in different ways and the designer’s desire.Having a circuit with high DC gain and an appropriate bandwidth in amplifiers is the main purpose of design and the main problem in design is achieving these two parameters simultaneously that are in contrast to each other. Namely, by increasing one of them, the other one will decrease, and another problem in design of amplifiers is low power consumption.In this thesis, the two-level amplifier are used with positive feedback and 0.18 μm technology for CMOS Transistor in order to solve the mentioned problems. Mentioned amplifier circuit is simulated by using of cadence simulation software.Simulation results suggests that the gain is about 107.7 dB, amplifier bandwidth is 39.48 MHZ and phase margin is 87.7deg and power consumption is 267.963μW that significantly improved compared with previous methods.

Keywords:

gain , bandwidth , positive feedback , fully differential two stages amplifier , power consumption