News from the ECE Department
Subscribe to the ECE News and Calendar RSS Feed
February 13th, 2012
Graduate Seminar
"Low Power Frequency Synthesis using FBAR/IC Integration"
Dr. Julie Hu
Postdoctoral Researcher
Electrical Engineering
University of Washington
When: Monday, February 13th, 2012 at 3:05 p.m.
Where: Warnock 2250
Abstract
Advances in semiconductor technology have stimulated unprecedented innovations in the development of wireless sensing and medical care products, particularly low-cost, small form-factor, wireless sensors and medical implantable devices. Today, integrated circuit technologies allow integration of analog, RF, and digital circuitry in a single chip. Low power consumption is crucial to successful deployment of these small devices since they must operate on limited energy budgets (none of those devices currently use scavenged power – it is just an idea so far). While the digital portion of the circuits have scaled well with the technology, analog/RF doesn’t benefit quite as much from smaller features. The major issues include low supply voltage, low device gain, and more seriously, on-chip inductors with low quality factor and inefficient silicon usage. In short, a new analog/RF design methodology is needed that takes advantage of technology scaling and benefits this emerging generation of wireless devices.
In this talk, I will discuss the benefit of using the high quality factor FBAR (Film Bulk Acoustic-wave Resonator) as a resonant element to replace on-chip LC tanks in RF designs and present a range of new circuit designs to overcome above challenges. I will focus on two relevant projects from my Ph. D. dissertation: an ultra-low power analog phase-locked loop, a low power divider-less all-digital phase-locked loop. I will demonstrate the power efficiency gain resulting from high Q RF frequency synthesizers. Experimental results will be presented and exciting future opportunities in low power wireless applications will be discussed.
Speaker Biography
Julie earned her Ph.D degree in March, 2011, from the Electrical Engineering in University of Washington, with an emphasis in analog and radio frequency circuit design. The title of her dissertation is "Low-jitter Frequency Generation Techniques for Low-power Applications". Her research interests fall in the area of low power frequency synthesis, low power RF transceivers, and low power wireless sensor circuits. Julie holds Master degrees in semiconductor physics and devices as well as in computer engineering. She started her career as a software engineer in Hewlett-Packard, where she developed a software tool (PCB netlist extractor) to allow diagnosis of EMI and analysis of signal integrity on PCBs. She started designing digital ICs in 2000 in Agilent. The designs included digital filters, data decimators, and fractional-n controllers for PLLs.