A Collection of Contemporary Research Articles in Electronics, Communication & Computation- Book ISBN- 978-81-948050-7-6

Authors: C. S. Sajin, T. A. Shahul Hameed 

Abstract: This paper presents the simulation of differential cascode amplifier, two-stage cascode amplifier and folded cascode amplifier in 90nm & 45nm, and its comparative review study with reported results. Cascode amplifiers render essential output impedance and diminish the impact of miller capacitance, thereby improving speed achievement. In this work, the performance parameters are optimized by respecting their tradeoffs, and the work aims at bandwidth enhancement. The bandwidth is raised by improving trans conductance and lowering the output capacitance. Here the circuit is simulated using cadence virtuoso tool and in gpdk technology. Amongst amplifiers simulated in this paper, the differential cascode amplifiers deliver well in terms of gain, and the folded cascode amplifiers manifest the best speed characteristics. The two-stage cascode amplifiers perform reasonably in terms of gain and frequency. The optimized simulation of differential cascode amplifiers in 45nm manifests 36 dB gain,15.8 MHz bandwidth, 300 MHz unity-gain bandwidth, and consumes very less power of 195nW. The two-stage cascode amplifier in 45nm exhibits 24.8  dB gain, 950MHz bandwidth and 6.5 GHz unity-gain bandwidth and these values prove the significance of the circuit in high- frequency applications. The folded cascode amplifier in 45nm results in frequency response with 3 dB frequency of 4.9 GHz and UGB of 18GHz.This value shows that the speed performance of folded cascode amplifier in 45 nm is superior over other simulated cascode amplifiers presented in this work and that reported in [1]. The simulated folded cascode amplifier in 45 nm consumes an area of 2.65µm x 2.65µm(7.03 µm2 ). It consumes 67µW from a 1V power supply.

Keywords: Folded Cascode Amplifier (FCA), Two Stage Cascode Amplifier(TSCA), Differential Cascode Amplifier (DCA), Unity Gain Bandwidth (UGB).