Date of Award


Publication Type

Master Thesis

Degree Name



Electrical and Computer Engineering

First Advisor

Dr. Chunhong Chen Department of Electrical and Computer Engineering


Engineering, Electronics and Electrical.




Passive RFID transponder is a tiny device that has unique ID information for communication with RFID readers and relies on the reader as a source of power supply. The main components of a typical transponder IC include antenna, analog front-end circuit and baseband processor, where the system clock is provided by a local oscillator. One of the biggest challenges for the oscillator is to ensure the lowest possible power consumption for passive RFID applications. A nano-power VCO capable of functioning as a local oscillator for the transponders is obtained by biasing the delay cells to operate in weak inversion region. Further power reduction is achieved by transistor sizing. Designed in a 90-nm CMOS technology, the proposed circuit oscillates with a power supply of 0.3V with frequency tuning characteristics and consumes only 24nW. The center frequency is 5.12MHz and the phase noise is -80.43 dBc/Hz at 10KHz offset.