Personnel

FICs - Prof. Philip K. T. Mok

Description

The ever-growing power demands of system-on-a-chip (SoC) designs for portable smart devices have brought up challenges for power management integrated circuits design. SoCs that embed many functional blocks on a single chip require each block to operate in a clean electronic environment, which means supply voltage for each block must be finely regulated regardless of its working status, whether doing extensive power-hungry computing or standing by in an ultra-low-power mode. In a conventional two-stage power scheme for an SoC, a global power bank, which is usually a high-efficiency (over 95%) switching converter, delivers power to multiple second-stage voltage regulators that are located near the loads. However, serious problems arise under this scheme, such as all regulators distributed over the SoC within the same voltage domain will experience disturbances when any block suddenly draws a large amount of current. However, the elimination of any of these disturbances, which depends on the ability of each near-load regulator, is not effective as those near-load regulators are usually not designed to work collaboratively. This proposed research aims to develop a new power distribution scheme which uses a homogeneous dc-dc converter grid or dc-dc regulator grid as the second stage in two-stage power conversion. With the introduction of homogeneous regulator grid, the new power distribution scheme can monitor and direct the dynamic power flow on the grid and enhance the load sharing within the grid. Methods will be developed for this multi-regulator environment that will reduce the complexity in design and allocation of multiple regulators, as well as improve the balanced load sharing within the regulator grid. As a result, it will realize fast transient response and reduce the disturbances on surrounding load characteristics for each regulator. In this project, based on the proposed grid structure, a systematic, fast load-sharing scheme will be developed and its effectiveness in enhancing load transient responses will be evaluated. The new distributed power supply scheme’s ability to adapt to more advanced technologies or upgrading in SoC scale will be explored as well in this project.

Source: RGC | ITF