Micro Power Radio Frequency Oscillator Design

 Nathan Pletcher, 2004 MS Thesis

Advisor: Jan Rabaey

Abstract:

Wireless transceivers for sensor network applications require designs that are both highly integrated and extremely low power. Deep sub-micron CMOS technology offers high levels of integration and opens up new frontiers in low voltage and current circuit design, making it a natural choice for implementation of these circuits.

In this work, two design techniques for ultra low power CMOS radio frequency (RF) circuits are investigated, with an emphasis on oscillators. First, the potential for RF oscillator design at very low supply voltages (0.5V and below) is investigated. Additionally, subthreshold device operation is explored as a potential method for reducing power consumption in modern CMOS processes.

To verify the design approach, a fully integrated LC oscillator is designed and implemented in a 130nm CMOS process. The circuit is designed to allow highly flexible testing of the low power oscillator across a range of supply voltages and bias conditions. Ultimately, oscillator operation with power consumption less than 0.2mW is demonstrated, with supply voltages as low as 300mV.