Power Supply IC Technology Contributes to Smaller Size and Lower Power Consumption of Electronic Equipment

Power supply technology is a basic technology that supports all types of electronic equipment. Switching power supplies, in particular, are characterized by small size, light weight and high efficiency and are the mainstream technology used in power supplies at present. In recent years, with the advent of an advanced information and communications-oriented society, trends toward personalization and mobilization have accelerated and demands are increasing for electronic devices that are smaller, lighter in weight and consume less power. Power supply technology is also entering an era of change. Having a long history of involvement with semiconductor devices for switching power supplies, Fuji Electric is now concentrating on power supply ICs (integrated circuits) as core devices that perform control functions. Fuji Electric’s power supply ICs fall into the two categories of AC-DC power supply-use devices that take a commercial AC line input and DCDC converter-use devices that are mainly used in battery-driven applications. These devices had previously been produced as commercial products using bipolar technology, but in response to market demands for lower power consumption and a combination of functions, a change to high-voltage CMOS (complementary metal oxide semiconductor) analog technology was initiated several years ago and at present, nearly all of Fuji Electric’s power supply ICs have completed the transition to CMOS technology. This paper introduces the technical and product development for power supply ICs and also discusses Fuji Electric’s future outlook for this field.