Abstract: This paper presents a review of the designs of different voltage reference circuits on the basis of different parameters such as Vref, supply range, power dissipation, temperature coefficient etc. The circuits reviewed are ultra-low power. Recent research in CMOS integrated voltage generators has resulted in the development of components that make possible the design of a high performance linear CMOS voltage reference generators with low output noise. In this paper, few of the designs are reviewed on the basis of the performance of the circuits.

Keywords: Voltage Reference, MOSFET, Current reference.