The SDC logo is based on one of the printed circuit board design techniques that is taught in our Concepts of Signal Integrity Design class. Sometimes, especially when using CMOS circuitry with large fanout, (large number of components connected to a single trace), it is necessary to balance the loading effects of multiple cicuit branches. This can be done by lengthening the printed circuit board traces that run to some of the components. This lengthening is achieved by routing the trace in a serpentine fashion. This is one of the techniques that came into use in the 1990's on systems running at speeds of about 100 MHz. Our logo is meant to illustrate the serpentine technique.

The metallic look of our logo was achieved using a three-dimensional animation program called Vue^TM, from e-on software.

Rendering a picture in 3-D is very different from drawing with the more-familiar 2-D drawing programs. Instead of drawing a picture, you create a model of each item in your picture, and then you position and place the models in 3-dimensional space. This is similar to positioning actors and props on a stage. In addition to the items in your picture, you also place a camera and one or more light sources into your 3-D space.

When rendering the picture, the software simulates a single ray of light, travelling from a light source, bouncing off of an object in the picture, continuing to the camera and through its lens, until it finally reaches a single point on the camera's digital film. This process is then repeated for every light source, for every object in the picture, and for every pixel on the digital film.

As you might imagine, there are a lot of light rays that must be computed! It can take several minutes to render a single scene, or an hour or more to render a short animation. But the realistic look of the final picture makes it well worth the wait.

(For efficiency, the light rays are actually traced in reverse, starting at the camera's film plane and working backwards toward the light source. Working in reverse is more efficient because the software does not waste time on light rays that never reach the film plane).

The earliest Ray-tracing algorithm was developed by Turner Whitted in 1979, and it was an extension of an earlier technique called ray-casting developed by Arthur Appel in 1968. (Source: Wikipedia). Back then, the calculations required the use of a supercomputer. These days, you can achieve the same results, or better, using a laptop computer!

Producing the SDC logo took roughly one day. Developing and positioning the graphical elements was the easy part. The time-consuming part was experimenting with positions for the camera and the light sources, to make the reflections look just right.

Tim A. Schreyer, "freelance inventor", is a senior electrical engineer with a lot of hobbies.

He worked for 13 years for Intel Corporation, where he was a member of the Senior Engineering Staff at Intel's system division in Hillsboro, Oregon. While at Intel, Tim developed strategies to manage signal integrity, electromagnetic interference and thermal effects on computer motherboards. He developed classes and taught them to engineers and technicians, and he managed a small engineering group that used his design strategies to develop computer motherboards. Tim was an active member in teams that developed the Pentium^® Processor "backside" cache bus, PCI, AGP and other system bus specifications.

Although primarily an electrical engineer, Tim's work and interests have led him to do quite a bit of computer programming, and he has learned and used more than a dozen computer languages throughout his career. The languages he has learned include earlier languages like Fortran-77, Univac Assembly, Cray Assembly, Motorola 6800 Assembly, Modula-2, AWK, C and Perl as well as more recent languages like C++, Visual Basic, Visual C++, Visual C#, SQL, Python, PHP and ASP. His current "favorite" languages are Visual C# and Microsoft Excel (which he naively considers to be a programming language).

Tim received his Ph. D. in electrical engineering in 1989 from Stanford University, where he conducted research on chip-level interconnect performance on VLSI integrated circuits. Tim's education and career give him a broad background in integrated circuit design, system design, solid-state physics, electromagnetic fields theory, mathematics, computer programming and business administration.

Tim's hobbies include barbershop quartet singing, landscape photography and videography, hiking, backpacking, and search & rescue. He has 20 years experience backpacking in the Pacific Northwest and American Southwest, and at last count, he has travelled overseas to 18 countries. Tim was one of the founding officers for Colorado Mounted Rescue, and he currently volunteers as a searcher and past-chairman of Upper San Juan Search And Rescue, Inc. in Pagosa Springs, Colorado.