How an Old Digital Dog Can Learn New Analog Tricks
October 10, 2019
| By: Ben Smith
Principal Member of the Technical Staff, Applications, Maxim Integrated
I have a confession: I'm not really an analog person.
For pretty much my entire career, I've been working with microcontrollers and hooking them up to other, mostly digital, blocks. Freed from the uncertainties that plague the analog world, I could build large, complex systems out of digital logic, content in the knowledge that as long as I didn't push things too far, I could connect pretty much any digital output to pretty much any digital input, and the system would "just work."
So, when I was asked to update some training that covered correcting gain and offset errors in amplifiers, my first response was, "I'm a digital guy, you know?"
And their response? "That's okay–everything's in the presentation. We just need you to read it!"
Well, that brief conversation started me on a little journey of discovery, the result of which is this amplifier gain and offset walkthrough of slightly more than 27 minutes duration. If you're like me, thinking you can just grab any old amplifier off the shelf and it'll probably work in your application, grab a cup of coffee and settle in–I think you'll find it enlightening.
It certainly was for me. Until I took this journey, if you'd asked me about the gain of modern amplifiers, I'd have said, "really high," and if you'd asked me about offset error, I'd have said, "really low." And at first glance, I'd have been right: gain of over a million is practically infinite, and offset measured in microvolts is practically zero.
See, that's the problem. In many modern applications, we're trying to isolate a tiny signal hiding in a noisy environment, our link budget may already be small, and just a tiny error at the input may be grotesquely magnified at the output. Fail to take that into account as you construct your gain stages, and your system may miss its design goals. And that's why you have to choose your amplifier carefully.
The good news is that Maxim has lots of amplifiers to cover every application. Whether you need power-up compensation, continuous compensation, or a chopper-stabilized amplifier, Maxim has you covered. The trick is knowing what you need and how to find it–and that's what this video is all about!
See, an old digital dog actually can learn new analog tricks!