Welcome to the special issue of the International Journal of High Speed Electronics and Systems on "High-Speed Mixed-Signal Integrated Circuits". Silicon, in particular MOS silicon, has rapidly become the de facto technology for mixed-signal integrated circuit design due to the high levels of integration possible as device geometries have shrunk to nanometer scales. The reduction in feature size has meant that the number of transistor and clock speeds have increased significantly. In fact, current day microprocessors contain hundreds of millions of transistor and operate at multiple giga Hertz. Further, this reduction in feature size has also had a significant impact of mixed-signal circuits. Due to the higher levels of integration the majority of ASICs have some analog component on them. Additionally, it has now become nearly mandatory to integrate both analog and digital circuits on the same substrate due to cost and power constraints. The eight manuscripts in this special edition focus on the some of the newer problems and opportunities offered by the small device geometries and the high levels of integration that is now possible.

This volume opens with an introduction to the analog issues surrounding accuracy concerns in nanometer CMOS by M. Flynn, S. Park and C.C. Lee. This paper reviews some of the causes of and trends in MOS transistor mismatch, and assess the implications for analog circuit design in the nanometer regime. Device matching improves as CMOS technology evolves but reductions in power supply voltages associated with the smaller geometries complicates design. Unlike digital circuits, in analog circuits lower power supplies result in higher power consumption due to thermal noise limits. However, new circuit techniques based on analog circuit redundancy can avoid the accuracy-power constraints related to device mismatch. To illustrate such techniques this paper focuses on data converters.