In August 2015 Erik Bruun - professor in our Electronics group - had his book about ’CMOS Integrated Circuit Simulation with LTspice IV’ published by the e-book publisher bookboon.com. In May 2016, the book has reached a total number of downloads in excess of 65,000, and the number of downloads per month still remains high.
“It started out as an attempt to turn some informal notes from my teaching into a format which could be used by more than just the few students that I am teaching”, Erik explains. But apparently, he has hit an unexpectedly large market. The number of downloads is orders of magnitude larger than the number of DTU students using LTspice.
Teaching circuit simulation
Erik has been using the circuit simulation program LTspice for his teaching in basic electronics and in analog integrated circuit design for some years. The program has a major advantage in being freely available from Linear Technology, not just in a limited student version, but in a full, professional version. Also, it is very easy to download and install on both Windows computers and Mac computers. However, there is only rather limited documentation available from Linear Technology, and students kept asking for guidance. Erik has described basic features of the program in his lecture notes and in problem solutions for students in basic electronics. But a more systematic description of the program was lacking, especially when it comes to using the program for simulating CMOS integrated circuits. Erik has developed this during the last few years, but rather than just publishing notes on CampusNet, he found that a wider distribution channel would be even better. And as the program is freely available, so should the book about the program be.
Free e-books
This is where the e-book publisher bookboon.com comes in. Bookboon.com publishes textbooks in business, management and engineering which are freely available for the user. They are paid for by advertisements which appear on roughly every third page in the books. Of course, this might be somewhat disturbing for the reader, but Erik found it much more valuable to be able to provide a free guide to a free program than to use a normal textbook publisher where the price of a similar book would probably be in the 50+ Euro level.
What is next?
The book about CMOS integrated circuit simulation contains a large number of exercises for the reader. In the book, answers are given to these end-of-chapter problems, but not the full solutions. So an obvious addition is a book presenting fully worked-out solutions to the end-of-chapter-problems. This is coming out in June 2016. And looking further into the future, a second edition of the book is planned as a new version of the LTspice program is expected to be launched later this year.
And who knows, by the end of June, Erik is retiring from his professor position – or as he puts it, he is being promoted to Professor Emeritus – and this may leave time for writing yet another textbook about CMOS integrated circuit design based on his long experience in teaching this discipline.