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Design-Oriented Analysis (D-OA) is a powerful engineering tool.  The name, D-OA, includes the word "Design"  but the power extends well beyond design engineering.  Maybe someday the name will change to something more inclusive, such as Understanding-Oriented Analysis (U-OA).  With understanding, design engineering and other types of engineering are more productive and more fun. 

The phrase "Design-Oriented Analysis" can be traced all the way back to the year 1964.  In that year, Dr. R.D. Middlebrook presented a paper entitled, "Design-Oriented Analysis of Feedback Amplifiers" at a technical conference.  Dr. Middlebrook continued to develop, apply and teach D-OA until very near his death, at about 80 years of age. Dr. Middlebrook passed away on April 16, 2010.

For the nominal fee of  $50 US, you can get a DVD containing audio/video and pdf documents of his course entitled "TECHNICAL THERAPY for Analog Circuit Designers."   Visit his website at  http://www.rdmiddlebrook.com/.   Historically, the development and application of D-OA has been strongest in the area of analog circuit design, and even more specifically in the area of switch mode power supplies.  This is no coincidence.  Dr. Middlebrook's work has been extensive in both of these areas.  The creator of this website, Garrett Neaves, became aware of Dr. Middlebrook's publications and courses during his ongoing experience as an analog integrated circuit design engineer.  Therefore, the initial focus and the likely future focus of this website is analog circuit design.  However, the reader is reminded that a D-OA approach is much more widely applicable than analog circuit design, extending beyond design and beyond electronics.

 Here is how Dr. Middlebrook defines D-OA on his website:

• Design is the reverse of analysis: one starts with the Answer (the Specification), and one has to work back to the beginning (circuit configuration and element values). Therefore, only analysis that can be worked backwards is worth doing. This is Design-Oriented Analysis.
   
•   Design-Oriented Analysis is the process of guiding and controlling the algebra so that the result is a Low-Entropy Expression, defined as one in which the terms are ordered, or grouped, so that additional insight is obtained into the relative importance of the various contributions to the result. This is the source of the additional information needed for design, and substitutes for the missing equations that would be needed to solve formally for the number of unknowns. 

The "Technical Therapy" course starts with  a very entertaining presentation of the motivation and background for the course.  You can hear chuckles from those in the audience when they hear Dr. Middlebrook describing the scenario of an engineer working on his/her first design project.  During that first design project, the engineer discovers that the analysis methods learned in college are nearly useless for the purpose of designing a circuit.  The engineer proceeds by finding some existing circuit and then modifying it by guessing (maybe an educated guess?) and then checking how the resulting circuit behavior compares to the target.  The chuckles are a kind of nervous laughter of those thinking, "Hey, I thought that was my secret.  I thought the other designers had a better understanding than me."   Dr. Middlebrook poses the question "If most of the stuff you learned in school, taught by professors turned out to not be much use, why are you here listening to another professor talking about the same old stuff? "  One answer is that this professor is able to articulate what actually happens in the design projects and meetings that the audience members have experienced at work.  For example, Dr. Middlebrook describes a circuit design review meeting.  This is a meeting in which the designer talks about the circuit that he is working on and the audience is supposed to be able to give meaningful feedback.  But with the guess and check method,  the audience is often not able to do much more than say "It looks like you are doing a lot of work. Continue. Don't forget that the layout engineer needs to have your finalized schematics this Friday."