Node65

Hello analog newbies. Welcome to Team Node65!

Analog design is often treated like a black box: you feed in a signal, you pray, and you get something out. Logic works… until your transistor stops behaving “nicely” and starts doing what it was born to do: be gloriously non-linear. The bad news is you can’t escape non-linearity. The good news is that’s the reason analog engineers get paid.

In this blog, we’ll build intuition from the ground up, starting with a single silicon transistor, then moving forward step-by-step until we can confidently understand and design circuits all the way up to an op-amp.

This won’t be purely theoretical. We’ll learn the way analog is actually learned: by simulating, breaking things, fixing them, and repeating. I’ll be using Cadence Virtuoso with TSMC 65 nm technology. If you’re using a different node or a different PDK, don’t worry — the recipe is the same. The numbers will change, but the thinking process won’t.

And that brings me to the best analogy for analog design: cooking.

No cooking book contains the “perfect” recipe that always works in every kitchen. You estimate, you taste, and then you do the most important step: sprinkle a little salt approximately until it feels right. Analog is the same. We start with first-order estimates, then we tune variables — bias points, device sizes, compensation, poles/zeros — until the circuit gives a “tasty” result. A great cook doesn’t become great by reading recipes all day. They become great by cooking every day. That’s exactly how we’ll do analog here: learn by doing, build intuition through repetition, and slowly turn the black box into something you can actually control.

If you’ve ever thought “analog is not for me,” consider this your invitation to rethink that. Let’s learn it properly — and enjoy the journey.