A fully integrated 2.4-GHz LC-VCO frequency synthesizer with 3-ps jitter in 0.18-μm standard digital CMOS copper technology

Abstract

In this paper, we present a fully integrated frequency synthesizer, using an LC voltage-controlled oscillator (LC-VCO) as the core oscillator. The synthesizer is designed to provide various output clock signals for a transceiver chip. Sampling clocks for on-chip analog-to-digital and digital-to-analog conversion modules are also generated, where low jitter is required. The synthesizer also includes an additional digital phase-locked loop and programmable fractional dividers. We present the general concept, special issues related to low jitter, and test chip results. The synthesizer achieves 3-ps rms long-term jitter on a 200-MHz output with 20-mW power and an area of 0.7 mm/sup 2/.