Managing Power Electronics: VLSI and DSP-Driven Computer Systems

Chapter 2

Power Management Technologies

2.1 Introduction

Power management is generally accomplished by a combination of small signal transistors acting as the brain, power transistors acting as solid state switches that control the power flow from the source to the load, and passive components like resistors, capacitors, and inductors, acting as sensing and energy storing elements. A semiconductor integrated circuit can incorporate on a single die a large number of small signal transistors as well as limited values of passive components (resistors, capacitors, and lately even inductors) and power transistors carrying a few Amperes. For larger levels of power, external discrete transistors built with specialized processes are utilized in conjunction with the IC. In this chapter we will see how ICs and discrete transistors require very different methods of fabrication. We will first discuss the integrated circuits typically incorporating the desired power management control algorithm and the process and package technologies utilized for their construction. Subsequently we will discuss the discrete power transistors, called to duty when the power levels cannot be handled monolithically by the integrated circuit, and the process and package technologies utilized for their construction.

2.2 Integrated Circuits Power Technology: Processing and Packaging

The power of the integrated circuit process lies in its ability to etch a high number of electrical components on a small silicon die ...