原创 Design of Analog CMOS Integrated Circuits

         Good analog design requires intuition,rigor,and creativity.As analog designers,we must wear our engineer's hat for  a quick and intuitive understanding of a large circuit,our mathematician's hat for quantifying subtle,yet important effects in a circuit,and our artist's hat for inventing new circuit topologies.

         Analysis and design of integrated circuits often require thinking at various levels of abstraction.Depending on the effect or  quantity of interest ,we may study a complex circuit at device physics level,transistor level,architecture level,or system level.In other words,we may consider the behavior of individual devices in terms of their internal eletric fields and charge transport,the interaction of a group of devices according to their eletronical characteristics,the function of several  building blocks operating as a unit,or the peformance of the system in terms of that of its constituent subsystems.Switching between levels of abstraction becomes necessary in both understanding the details of the operation and optimizing the overall performance.

         Many device and circuit parameters vary with the fabrication process,supply voltages and ambient temperature.We denote these effects by PVT and design circuits such that their performance remains in an acceptable range for a specified range of PVT variations. Robust analog design in CMOS technology is a challenging task because device parameters vary significantly from wafer to wafer.