Design Considerations for Integrated DC-DC Converters

With the increasing needs to incorporate more complex mixed-signal controller for switched mode power supplies, CMOS compatibility becomes a very important consideration in monolithic Smart Power ICs. Designers need to examine various design considerations for the implementation of integrated DC-DC converters, which include switched mode power supply topology, digital vs. analog controller, power conversion efficiency, dead-times, choice of components, and power transistors for the output stages. In particular, EDMOS device structures, fabrication techniques and compatibility issues with CMOS process must be considered. Key device characteristics such as ruggedness, on-resistance, gate capacitance, switching speed and layout strategies are required for optimum power conversion efficiencies. Some research has been carried on integrated DC-DC converters with novel features such as segment output stage, digital spread spectrum for EMI suppression, dead-time control. The benefit of the segmented output stage has been demonstrated via a true power management system for portable audio applications.

To read more about the topic, please visit http://www.vrg.utoronto.ca/~ngwt/

Write-up above is adapted from an abstract of seminar by Prof Ng Wai Tung, University of Toronto.

Dr. Hor Poh Jin

DreamCatcher Principal Consultant

Jan 2010