Integration of a power supply for system-on-chip

Integrating the power supply and signal processing circuit into one chip is an important step towards achieving a system-on-chip. This paper reviews and looks at the current technologies and their trends for power supply components such as DC-DC converters, intelligent power LSIs, and thin-film magnetic devices for the system-on-chip. A device structure has been proposed for the system-on-chip that is based on a quasi-SOI technique, in which the buried oxide layer is partially removed from the SOI substrate. In this structure, the CMOS devices for the digital signal-processing circuit and the bipolar transistors are formed in a conventional SOI region, and the CMOS analog devices and high-voltage devices are formed in a quasi-SOI region.