tailieunhanh - Lecture Electrical Engineering: Lecture 18 - Dr. Nasim Zafar

The main contents of the chapter consist of the following: Introduction, the operating point and biasing stability, fixed-bias circuits, fixed bias with emitter resistance, voltage-divider bias circuits. | Dr. Nasim Zafar Electronics 1: EEE 231 Fall Semester – 2012 COMSATS Institute of Information Technology Virtual campus Islamabad Transistor Biasing Circuits and Thermal Stability. Lecture No: 18 Contents: Introduction The Operating Point and Biasing Stability Fixed-Bias Circuits Fixed Bias with Emitter Resistance Voltage-Divider Bias Circuits 2 Nasim Zafar References: Microelectronic Circuits: Adel S. Sedra and Kenneth C. Smith. Electronic Devices : Thomas L. Floyd ( Prentice Hall ). Integrated Electronics Jacob Millman and Christos Halkias (McGraw-Hill). Electronic Devices and Circuit Theory: Robert Boylestad & Louis Nashelsky ( Prentice Hall ). Introductory Electronic Devices and Circuits: Robert T. Paynter. 3 Nasim Zafar References for this Lecture: Chapter No. 9 Microelectronic Circuits: Adel S. Sedra and Kenneth C. Smith. Integrated Electronics : Jacob Millman and Christos Halkias (McGraw-Hill). 4 Nasim Zafar Objectives: Discuss the concept of dc biasing of a transistor for the linear operation in the active region. Establish an operating point Q in this active region to provide appropriate potentials and currents. Analyze the voltage-divider bias, base bias, and collector-feedback bias circuits. Establish a criterion for comparing the stability of different biasing circuits. 5 Nasim Zafar 5 Transistor Biasing Circuits: an Introduction Biasing refers to the establishment of suitable dc values of different currents and voltages of a given transistor. Through proper biasing, a desired DC operating point or quiescent point; Q-Point of the transistor amplifier, in the active region (linear region) of the characteristics is obtained. The goal of amplification, in most cases, is to increase the amplitude of an ac signal without distortion or clipping the wave form. 6 Nasim Zafar Transistor Biasing Circuits: an Introduction The selection of a proper DC operating point or quiescent point, generally depends on the following factors: (a) The amplitude of the . | Dr. Nasim Zafar Electronics 1: EEE 231 Fall Semester – 2012 COMSATS Institute of Information Technology Virtual campus Islamabad Transistor Biasing Circuits and Thermal Stability. Lecture No: 18 Contents: Introduction The Operating Point and Biasing Stability Fixed-Bias Circuits Fixed Bias with Emitter Resistance Voltage-Divider Bias Circuits 2 Nasim Zafar References: Microelectronic Circuits: Adel S. Sedra and Kenneth C. Smith. Electronic Devices : Thomas L. Floyd ( Prentice Hall ). Integrated Electronics Jacob Millman and Christos Halkias (McGraw-Hill). Electronic Devices and Circuit Theory: Robert Boylestad & Louis Nashelsky ( Prentice Hall ). Introductory Electronic Devices and Circuits: Robert T. Paynter. 3 Nasim Zafar References for this Lecture: Chapter No. 9 Microelectronic Circuits: Adel S. Sedra and Kenneth C. Smith. Integrated Electronics : Jacob Millman and Christos Halkias (McGraw-Hill). 4 Nasim Zafar Objectives: Discuss the concept of dc biasing of a transistor