第2章 偏置.pdf

SE CMOS Analog IC Design CMOS Analog IC Design NANJING Chapter 2 Chapter 2 Basing Circuits Basing Circuits jwu@seu.edu.cn Version-II, 2012,09 1 wujin SE Focus on the Contents Focus on the Contents NANJING Biasing: Constant current/Voltage generation; V ⇔I -- Single branch, the simplest biasing -- Multi-branches coupled biasing (Linear/Nonlinear CM); L-CM for current transportation; NL-CM for current definition; -- Dynamic property. Current Mirror -- Current Source/Sink for transfer, used in out biasing -- Cascode CM used for impedance boosting Excellent or Ideal biasing -- Better in matching when delivering current; -- Stable when VDD, temperatures are varied 2 wujin SE Ideal Biasing: Voltage/Current Source Ideal Biasing: Voltage/Current Source NANJING Biasing for a MOSFET: Static IDS and VGS provided circuit - To generate a stable IDS by a fixed VGS when located at S.R. or - To generate a stable VGS by a fixed IDS when located at S.R. PVT insensitivity: Process, Voltage, Temperature; Endless V/C Reference: V/C Sourc