The "Why"

In previous post I talked about my background and how I came to learn about Signal Integrity. Now I want to talk about the why I liked it so much.

Electronics can be broadly divided into the Analog and Digital worlds. During junior year, most students start finding their area of concentration, and it seemed like most went for either the purely digital or the analog tracks. For me, I liked them both equally, and couldn't see myself just going into one single route. By the time I graduated, the best compromise I could find was DSP, and I even took some graduate courses about it. On the downside, DSP may require a lot of coding for which I was not particularly fond of. At that same time I had started with my first engineering job and found Signal Integrity.

Signal integrity was just what I was looking for as it deals with digital signals but with an understanding that those signals need to interact with the real world. The real world - for the most part - is analog.
This was no mystery before, however, before it didn't really matter.

What changed?

In 1999, the state-of-the-art Pentium II processor had a max clock speed of 450 MHz and the front side bus speed was 100 MHz. Compared to today's processors... I'd say not impressive.

Ten years later, the first iPhone had very similar specs. The number of electronic devices with an embedded computer increased dramatically, in addition, the consumer's appetite for data transfer and faster devices seems to have no end.

Photo by katerha

Just as a car going down the road at 5 mph is more maneuverable than the same going at 100 mph, slower signals are easier to send from one computer to another. At 5 mph, there's no need for a car with ABS, ESC, etc., but if you're driving at 100 mph, you're more likely to make it in one piece at your destination with all those extras.

After my first signal integrity class, I realized something that is best expressed in an anonymous quote Eric Bogatin worte in his book:

"There are two types of engineers: those who have signal integrity issues, and those who will."

This is a nice video showcasing the new Thunderbolt technology that provides 10 Gbps speed! I was fortunate to witness all the signal integrity work needed to achieve this incredible speeds.