Active Filter Cookbook

There's a lot to be said in favor of this book, I must acknowledge right up front. It does contain quite a few tabulated filter designs, and Mr Lancaster teaches a fairly straightforward approach to selecting from among them and scaling them to fit the user's needs. The print quality is good, too.On the other hand, it is a less complete book than I remembered it being from the days when I could still find my original copy. There are some gaps in treatment of notch filters, for instance, and less thorough coverage of some other types than I would have liked. I'm also not sure why he shunned everyday filter terminology like "Butterworth" and "ripple" in favor of dumbed-down alternatives like "flattest response" and "dips." And, being yet another reprint of the Second Edition, there has been no effort to update information on better op-amps that are available now, or to modernize the active filter applications that wrap up the book.Add to that the downright HEFTY price tag for this relatively slim reprint! Taking those reasons together, if I'd had the opportunity to glance through this volume in a store before buying, I probably wouldn't have done so. I ordered it more for sentimental reasons than anything else, but now that I can once again see its limitations for myself, I realize I would have been far better off putting that money toward a newer filter design book, such as the latest edition of Williams and Taylor.On the other hand, if you need the easy to use cookbook kind of information this book contains, and you do not foresee buying more than one book on the subject of active filters any time soon, then this book might very well be worth the price to you. What it DOES contain would be hard to find in any single other book. You'd probably have to search through two or three other works, and who knows how much you'd spend doing that.So, bottom line, I think it's fair to say that if you're looking for an all-in-one general resource on electronic filters, this is the one to have despite the price. But if you already have some other filter handbooks and a background in the subject, this one might not be a very good dollar value for you.

Don Lancaster is a very good writer, and has focussed on what really matters for anyone designing analogue active filters. At 240 pages, this book has all the design guidelines, mathematics and practical tips for the popular single-amplifier biquad (SAB) circuits such as Sallen-Key and Multiple-FeedBack (MFB), and 3- or 4-opamp circuits such as State-Variable designs; it covers cascading multiple sections, with many practical examples up to 6th order filters; it covers bandpass, low-pass and high-pass active filters, plus "just enough" mention of notch and Cauer/elliptical filters, as well as filter applications and digital tuning, etc... but the edition I have - the 1995 - is a bit too old to cover some of the more recent developments. No mention of switched-capacitor filters (well, the MF10C has come and gone in popularity, so no problem there), but no mention of any digital filter techniques... even so, you probably want that in a separate book; this remains a good introduction, very useful as it is, providing an extremely good grounding in theory - such as damping (transitional Thompson-Butterworth an all that), normalization/scaling, "s-plane" equations, etc. The practical side is fully covered (e.g. "You can NOT build a stable, high-Q, easy-to-tune, single-[amplifier] bandpass filter"); sensitivity of component variation is covered well.The book is physically and conceptually the "right size" - with no "waffle"; many university textbooks may be larger, and cover a few obscure extra filter circuits, but 90% of designers will never need them in their work. It is much more useful than (although covers les filter types, and slightly less up-to-date than) Lenk's "Simplified Design of Filter Circuits", which is about the same size.It would be nice to see a new edition (although I am happy enough with what the 1995/6 edition has); it could be improved slightly by having some of the alternative/family names for filter circuits (such as KRC and VCVS) listed, and a few (very few) extra comments could be made as to why you would avoid certain circuits. It would also be nice if a bit of colour was used to clarify some diagrams, and perhaps have the chapter and subsection heading repeated at the top of each page. All that is relatively unimportant - basically: don't mess with perfection, this book would be worse if it tried to cover much more than it does (but it would be nice to see an end to the CD4016 being called a "new" development).

A great read full of masterful material on filters, somewhat general but unfortunately limited outside of audio frequencies. I didn't know enough to know what I was getting into, but I was hoping for more applicability to radio frequency filters, but I am now learning that RF requires more sophisticated and sometimes expensive approaches. Oh well, still a great book for what it does contain.

This book is by no means complete.In chapter 9 he apparently ran out of enthusiasm, no notch filters anywhereWhere are the Cauer filters?FDNR filters (frequency dependent negative resistance) are not mentioned with a single word.A lot of other filter circuits are plain missing.This book was written probably over 30 years ago. Even the new editions contain references to the 741This book is seriously old fashion. Virtually all the info you can get online for free.Worth about $5, no more

This is one of the better books on filters, Lancastor actually knows what he is talking about with too much technical "junk" that make it look like it is a great book. Some authors use a lot of "junk" that really does not say much. It is well written compared to another author. This book is not confusing, or boring.

All of the ins and outs of filter design using opamps

Electronic filters is a very specialised subject and it’s surprising how many electronics engineers know nothing about them... including me. I recently tried to learn about active filters from the Internet with disappointing results. Seeing this book on sale at a reasonable price I decided to give it a try. The first two chapters are very relaxed and ease you into the book quite well. Unfortunately the main body of the book reeks of jargon which is poorly explained. My impression of the book is that it is intended for people who know the subject and just need a reminder to get them up to speed again. The information is there but it is hard work making sense of some bits of it. I ground to a complete standstill about halfway through and played around with the circuits on SPICE with encouraging results. I’m currently building low pass filters on breadboards with a level of understanding I never achieved using the Internet articles. It’s hard work but worth the effort.

This book covers most classic types of active filter and gives you the tools to design the response that you want. It also has a good description of how to impedance scale the filter to adjust the frequency.Highly recomended.

It is a comprehensive guide to Active Filters.It is very informative and clarifies the basics of Active Filters and provides the building blocks of using Active Filters to create complex solutions.

I purchased this text only for general guidelines. There are too many specifics in designing a filter such as tolerance, and other parameters which gives less then perfect results. I always turn to hardware in designing active filters, and I never use Spice. Don does inform the reader of limitations on many examples in the book, with reduced complexity to calculate the -3db point(s) in Band Pass, Low Pass, High Pass and Multiple Feedback Active Filters. With most electronics design equations, the math is overwhelming, and I don't think it will give any good results without experimenting with the filter first. One good piece of advice I can pass along; Don't use a breadboard designing Active Filters; The capacitance between each connection point is real problem. The bandwidth and the Q factor are reduced, and the frequency cutoff is not what you expect. While Don's book is very good, I wouldn't suggest this title to a newbie in Electronics. A advanced subject for electrical engineers.

This little but complete book Is a must to have if you want understand how filters work and how to build them, all the filters type are covered in great detail with all the tabs for normalization and component values. A good and shot treatment of op amps is present and I’ve found it useful to repeat some things about. A great tool for the lab!