Low Power Low Voltage Amplifier for removal of offset and Noise

Abstract

The biggest challenge for analog designers in CMOS technology is to remove the offset and flicker noise. Ideally an amplifier should produce zero as output, when its differential input signal is zero. In practical at the output, some offset voltage or current has been present. Noise also has become a giant problem in CMOS technology when it is compared to its previous technologies like bipolar technology. Today noise is the most important issue for CMOS platform. Any undesirable signal which interferes with desired signal is called noise. Mostly it deteriorates the signal’s inherent characteristics. It decides the minimum input signal value which can be accurately measured. There are a number of sources from where noise can originate. When the signal magnitude is large compared to the system noise, then noise does not play any momentous role, but when signal of interest is comparable to the system noise, then it becomes really tedious to distinguish between noise due to devices and the signal of interest. Thus, offset and noise are major design constraint. Our aim in this thesis is to design a low power low voltage amplifier system with emphasis on offset and flicker noise removal circuitry, which operates using signals of low frequency and amplitude and provides a necessary gain without introducing significant noise from the devices, especially noises that are dominant in low frequency region.