Novel Technique to Implement Low Power Differential Delay Cell Ring VCO with Variable Centre Frequency

Abstract

Ring VCO with variable center frequency incorporating the design of differential delay cell working at low power is illustrated in the current research work. Concept of variable frequency with low power consumption is a novel VCO implementation technique. A differential delay cell is used to generate variable frequency to design a ring VCO at 32 nm technology operated at 1.2 V power supply voltage to achieve low power and low phase noise characteristics. Five stage ring VCO is designed with switches, to ensure that one stage works at a time, keeping two stages off. This switching of stages is dependend on the desired frequency of operation by the VCO. The proposed research work also facilitate the additional computation of width and length of PMOS and NMOS transistor along with the computation of optimal parameters. At 1 MHz offset frequency, the proposed VCO achieves phase noise of - 105.53 dBc/Hz with minimum power consumption of 1 mW. The proposed VCO is poised to act as a major building block of a multi-standard wireless communication system such as GSM, Blue tooth, and 802.11g ZigBee applications.