Prof. Fayed Presents a Tutorial at the 2019 IEEE ISCAS
Prof. Fayed will be presenting a tutorial entitled "On-Chip Dynamic Power Supplies for Mixed-Signal SoCs" at the 2019 IEEE International Symposium on Circuits and Systems (ISCAS), Sapporo, Japan, May 2019.
The diminishing returns of semiconductor technology scaling in terms of power reduction is forcing the electronics industry to shift from the traditional approach of using a few centralized static power supplies to power a System-on-Chip (SoC) to a numerous distributed dynamic power supplies approach. In this approach, the SoC is divided into sub-components, each with its own independent on-chip power supply that is dynamically adapted to the real-time demand of each sub-component. As a result, the overall power consumption of the SoC can be significantly reduced. However, such approach requires a large number of dynamic on-chip power supplies, and it becomes quite challenging to implement them in a size- and cost-effective manner while also maintaining high power conversion efficiency, particularly in nanometer CMOS technologies where the voltage rating of transistors is quite low compared to Li-Ion battery levels. This tutorial will present the various techniques used to implement a large number of on-chip dynamic power supplies in mixed-signal SoCs, along with a discussion of the advantages and shortcomings of each technique taking into account factors such as design complexity, silicon area, efficiency, and passive components requirements. The tutorial will start with a brief overview of the concept of distributed dynamic powering of SoCs, followed by a short review of the basic operation of buck converters and the role of the switching frequency in the dynamic behavior and passive components sizes. The tutorial will then focus on high-frequency buck converters with on-chip passives, and multi-frequency SIMO buck converters with on-chip outputs. This includes techniques for implementing on-chip inductors and capacitors, power switches, and gate-drive circuits. The tutorial will be concluded with a brief discussion of future trends and the likelihood of various techniques to be adopted in the industry.