Article: How Can Digital Beat Analog?

Submitted By: Ajeet Khurana

I studied computer engineering in the late 80s. Though digital electronics had been around for a long time, it still retained some novelty.

As budding engineers we were in a dilemma: Why was digital electronics considered so cool and why was analog electronics considered seriously yesterday?

Of course there was no doubt in our mind that digital was the way to go, but the question still remained: Why?

Was it not true that in analog transmission, you could transmit any value, while in digital transmission, it was typically about binary transmission. And binary transmission means a bunch of zeros and ones. What could be the fun in that?

For instance in analog transmission, if I wanted to transmit the number 254, I would simply send it as 3 digits, a two and a five and a four. But in digital, specifically binary transmission, it would have to be 8 digits, i.e. 11111110, i.e., a series of seven ones and then followed by one zero.

I have been talking about binary transmission when talking about digital, because they are not the same thing. Binary transmission is just one type of digital transmission. There can be many others. For instance there can be trinary, which would transmit zeroes, ones, and twos. You get the idea.

But binary has turned out to be the most popular. This is because, in creating electronic circuits, you can very easily create switching circuits that will have a high voltage, i.e., a one and a low voltage, i.e., a zero.

This makes the digital electronic circuits efficient and low priced.

So, back to the original question. Why is analog not as good as digital? Are we missing something? Did out engineering teachers miss out on teaching us about some important part of the deal here? For instance, could it be about economics and not about electronics at all?

With our brain muddled with such thoughts, questions, and queries, we approached various teachers and gurus. Though they all knew that digital was obsolete, there were few who could give us more than standard party-lines. Of course there were the old-timers who stood staunchly behind the power electronics based on the analog paradigm.

It was the belief of these old-timers that the real electronics was the power electronics with vacuum tubes and a whole lot of heat. They told me of huge factories and industrial units that ran on these power electronics.

They pooh-poohed the latest fads revolving around digital electronics as a fad that was not worth more than making doorbells or kids projects. Probably that is all that they were exposed to in the name of digital electronics.

Now that two decades have passed, we have answered many of our early questions, but we have also created new and tougher questions.

That a hell of a lot of intelligence can be passed on using digital electronics is now easily accepted. That we do not need to have circuits with wires, but that we can actually draw circuits on boards, called Printed Circuit Boards, is also easily acceptable. Thankfully engineers today don't have to ask the same questions that we had to ask.