In my digital design class, we have started building character drivers for an embedded Linux OS on an ARM chip (ZYBOZ7-10 board). So far all we’ve done is create an integer multiplier in hardware and then interact with it from software running in the OS but I thought it was pretty neat 🤓

Update on Analog Design final project: We realized we need very low biasing current in our error amp (like super duper low), so we’re trying to use this “dynamic biasing” technique which gives the circuit more juice when necessary and scales back otherwise. Looking good so far. Paper for reference

Been out and about. Coming up on the end of the semester, so it’s grind time. Adv Analog project will be an LDO (1.6V out, 180nm) and perhaps a bandgap reference to go with. Gotta study PID controllers for controls. Last lab in digital design is a char device driver in Linux. Stay tuned

Advanced Analog lab today was on the design of a 2 stage folded cascode AB amplifier. The trick with this one is properly biasing everything and getting the Monticelli transistors to properly copy the AC signal to both branches. I also added Miller caps at the output to stabilize everything

Been grinding on work stuff the past few days. Studied for Controls Theory midterm tonight. Feeling pretty good about it. Supposedly it’ll be a block diagram simplification, a second order system analysis, and 3 physical system modeling questions 🤞

Microcontrollers lecture was schmedium interesting today. The prof introduced Linux and the concept of a kernel. I do like to hear different interpretations of the Linus Torvalds story though

A few things on the agenda today:
- Watch Microcontrollers lecture
- Work on Formal Verification stuff
- Work on UVM driver design
- Study physical system modeling for Controls Theory
- Run 10 miles (RIP)

Question of the Day: Is EMI more of a concern when using very big resistors or very small resistors?

In other news, my controls theory prof went over the Nyquist Stability Criterion today, and that bad boi is a doozy. This won’t be on the midterm next week but I’ll definitely need to look it over before starting the homework.

What’s up party people. Adv Analog lecture was on Class D amplifiers. Pretty cool concept. Very similar to buck converters so they’re highly power efficient. It does feel like their bandwidth might be limited to lower frequencies though. Big midterm next week so gonna grind this weekend

Just finished up my control theory homework for the day. The last problem asked us to find all values for Kp and Ki (PI controller) for which the system is stable. A bit tricky but not too bad (using Routh-Hurwitz)

In other news, I’m really enjoying my controls theory class. Yesterday, we reviewed Bode plots and using the Routh-Hurwitz criterion to determine Bounded-Input Bounded-Output stability. I think this’ll be uber useful in my analog design classes. Here’s a Bode plot if you’ve never seen one 🤓

In case you thought I know what I’m doing, I got absolutely thrashed by the assignment today. It was a class-AB fully differential amplifier. I couldn’t figure out the proper biasing scheme, so my job for tomorrow will be sussing that out :(

2 weeks ago my advanced analog prof gave an assignment on ring amplifiers. They’re like ring oscillators, but you stabilize them by creating a “deadzone” in one of the internal nodes. These scale better with smaller processes. Assignment was based on this paper (ieeexplore.ieee.org/document/637...)

Figured I’d use this as a study tool/something to do when bored. Just going to talk about what I’ve been up to in my classes 🤓