Smart power and high voltage integrated circuits and related MOS technologies

Abstract

The state-of-the-art of high voltage and integrated power circuits in MOS technology is presented. In the introduction, the evolution of these integrated structures is described, their major advantages over the discrete device solution are recalled and the issues concerning integration are addressed. The structures of the various devices realized in MOS technology and used as power switches in integrated circuits are reviewed. The two main families of circuits currently developed are considered, i.e. (i) smart power technologies including one or several (common drain) power switches having a vertical configuration, integrated with their control and protection circuitry and (ii) high voltage integrated circuits in which the power devices are lateral, of low current capability and where the control circuits (CMOS or bipolar) may have a higher integration density. The major functional issues related with the design of a smart power switch are presented. The main building blocks, in particular the thermal limit circuitry as well as the bias stabilized networks, are detailed at the transistor level. It appears that the involved analog circuitry can be properly stabilized with respect to electrical fluctuations as well as to process related parameter variations and instabilities.