DESIGN AND ANALYSIS OF LOW POWER PSEUDO DIFFERENTIAL CLASS-AB TELESCOPIC OPERATIONAL AMPLIFIER

D. S. Shylu, D. Jackuline Moni, Neenu Brigit Francis

Abstract: In this paper, the design of a pseudo differential class-AB cascoded telescopic op-amp for a 10-bit pipelined ADC is presented. A pseudo differential class-AB telescopic op-amp is used for the ADC architecture because of its large signal swing and high power efficiency. To further enhance the dc gain of the pseudo differential class-AB cascoded telescopic op-amp, two additional load capacitors are used. This proposed amplifier is designed in 180nm CMOS technology, and the simulation results show rail-to-rail input and output swings. With the modified pseudo differential class-AB cascoded telescopic op-amp the DC gain obtained is 43.41dB. The Common mode Rejection Ratio (CMRR) is 43.4dB, 91.19747° phase margin, 165.4544V/µs slew rate with 8-pF load capacitor and the power consumption is 0.4mW.

Keywords: ADC, CMRR, op-amp, pseudo-differential, slew rate, telescopic.

DOI: https://doi.org/10.15623/ijret.2014.0319044