《chapter_4single stage IC amplifier(for IT Class)》.ppt

SJTU Zhou Lingling Outline Introduction Biasing mechanism for ICs High frequency response The CS and CE amplifier with active loads High frequency response of the CS and CE amplifier The CG and CB amplifier with active loads The Cascode amplifier The CS and CE amplifier with source(emitter)degeneration Introduction Design philosophy of integrated circuits Comparison of the MOSFET and the BJT (Self-Study) Design Philosophy of Integrated Circuits Strive to realize as many of the functions required as possible using MOS transistors only. Large even moderate value resistors are to be avoided Constant-current sources are readily available. Coupling and bypass capacitors are not available to be used, except for external use. Design Philosophy of Integrated Circuits Low-voltage operation can help to reduce power dissipation but poses a host of challenges to the circuit design. Bipolar integrated circuits still offer many exciting opportunities to the analog design engineer. Biasing mechanism for ICs MOSFET Circuits The basic MOSFET current source MOS current-steering circuits BJT Circuits The basic BJT current source Current-steering Biasing mechanism for ICs(cont’d) Current-mirror circuits with improved performance Cascode MOS mirrors A bipolar mirror with base-current compensation The wilson current mirror The wilson MOS mirror The widlar current source The Basic MOSFET Current Source The Basic MOSFET Current Mirror Output Characteristic MOS Current-Steering Circuits The Basic BJT Current Mirror A Simple BJT Current Source. Current Steering Current-Mirror Circuits with Improved Performance Two performance parameters need to be improved: The accuracy of the current transfer ratio of the mirror. The output resistance of the current source. Cascode MOS Current Mirror Current Mirror with Base-Current Compensation The Wilson Bipolar Current Mirror The Wilson MOS Current Mirror The Widlar Current Source High Frequency Response The high-frequency gain function Determining