Courses » Analog circuits

Analog circuits


This course is an introduction to amplifiers using transistors. Students will be introduced to MOS transistors, their characteristics, techniques for biasing them, and amplifiers using them. The basic transistor amplifier stages are seen as realizations of different controlled sources using negative feedback. Small- and large-signal characteristics of each amplifier will be discussed. At the end of this course, students should be able to recognize and analyze the basic amplifiers and biasing arrangements using MOS transistors.

Important For Certification/Credit Transfer:

  • Weekly Assignments and Discussion Forum can be accessed ONLY by enrolling here(Scroll down to Enroll).
  • All of the content(lectures, discussion forum, assignments) are available at no cost.
  • Final Exam (in-person, invigilated, currently conducted only in India) is mandatory for Certification and has INR Rs. 1,100/- as exam fee.


Typical 1st and 2nd year EE curriculum. Specific pre-requisite courses are:

1. Basic Electrical Circuits
(e.g. http://nptel.ac.in/courses/117106108/ )

2. Networks and Systems
(e.g. http://nptel.ac.in/courses/108106075/)

4682 students have enrolled already!!


Nagendra Krishnapura is an associate professor in the VLSI group of the department of Electrical Engineering of the Indian Institute of Technology, Madras. He works in the area of analog and mixed-signal integrated circuits and signal processing.

He graduated with a Ph.D. from Columbia University, New York in Oct. 2000. He obtained his B. Tech. degree in Electronics and Communications Engineering from the Indian Institute of Technology, Madras, in 1996. Between 2000 and 2005, he worked as a senior design engineer at Celight, Inc. and Multilink(later Vitesse Semiconductor) where he designed integrated circuits for high speed communications. From 2003 to 2005, he was an Adjunct Assistant Professor and taught courses on Analog Circuit Design at Columbia University.


Week Unit contents
1 Course introduction; Need for nonlinear circuits; Incremental analysis of nonlinear circuits; Diode and its models; Incremental picture of a two port nonlinear circuit
2 Constraints on y-parameters and large signal characteristics to obtain a high gain; MOS transistor and its characteristics; AC coupling network to add signal to bias; AC coupling at input and output; Common source amplifier
3 Output conductance of a MOS transistor; Inherent gain limitation of a transistor; Sensitivity of gm to transistor parameters; Biasing a transistor at a constant current; Drain feedback configuration; Current mirror
4 Common source amplifier using drain feedback; Common source amplifier using current mirror bias
5 Common source amplifier using source feedback bias; Using a resistor instead of a current source for biasing; Further biasing techniques; VCVS using a transistor; Source follower biasing
6 CCVS using a transistor; CCVS using an opamp; Biasing a CCVS; Emitter degenerated amplifier
7 Common gate amplifier and its biasing; VCCS using a transistor and its biasing
8 pMOS transistor and its small signal model; Biasing a pMOS transistor; Converting nMOS circuits to pMOS; Amplifiers using a pMOS transistor
9 CS amplifier with active load; CMOS inverter
10 Differential pair with current mirror load; Single stage opamp
11 Two stage opamp; Compensation; Opamp models
12 Bipolar junction transistor-large and small signal models; BJT circuits- Biasing; Common source amplifier; Emitter follower

  • The exam is optional for a fee.
  • Date of Exam: 28 October 2018(Sunday)
  • Time of Exam: Morning session 9am to 12 noon; Afternoon session: 2pm to 5pm
  • Registration url: Announcements will be made when the registration form is open for registrations.
  • The online registration form has to be filled and the certification exam fee needs to be paid. More details will be made available when the exam registration form is published.
  • Final score will be calculated as : 25% assignment score + 75% final exam score
  • 25% assignment score is calculated as 25% of average of  Best 8 out of 12 assignments
  • E-Certificate will be given to those who register and write the exam and score greater than or equal to 40% final score. Certificate will have your name, photograph and the score in the final exam with the breakup.It will have the logos of NPTEL and IIT Madras.It will be e-verifiable at nptel.ac.in/noc.