Kevin Fronczak
Analog Circuit Designer



Home Automation with Home Assistant
Ever since my wife and I purchased our first home in 2014, I’ve been obsessed with home automation. I started with a few GE Link lightbulbs connected to a Wink Hub and pre-ordered an Amazon Echo with the hunch that they would eventually add in functionality to control my Wink Hub vias voice (the... Read more

DIY Heart Rate Monitor Using Your Smartphone
Recently I’ve been quite interested in biomedical sensors, namely Photoplethysmogram (or PPG) sensors. Essentially, a PPG takes advantage of the optical properties of skin to measure the rate of absorption or reflection of different wavelengths of light. A clinical PPG device is typically clamp... Read more

Levitation Clock
I’ve been meaning to post this for awhile, but better late than never I guess. For my senior design project in college, myself and two buddies of mine, Trong and Holden, (all of us nearly done with our Master’s degrees at the time) decided to build a clock… but no ordinary clock, no. We wanted to... Read more

Optimization Algorithms for Circuit Design
Over this past summer as I was wrapping up my Master’s thesis, I was taking a class involving the study of AI algorithms. Due to my thesis work involved switched DC-DC converters, I had the idea of implementing a Genetic Algorithm in order to design a Boost Converter (this was a graduate class so... Read more

Stability Analysis of Boost Converters for ICs
I recently completed my Master’s Thesis entitled “Stability Analysis of Switched DC-DC Boost Converters for Integrated Circuit” (August 2013). My defense slides can be found here. Here is the abstract: Boost converters are very important circuits for modern devices, especially battery-operate... Read more


One thing I really feel was lacking in my education was a good treatment of Z-domain circuits and analysis. Although, maybe it wasn’t lacking and I just didn’t appreciate the applications of it. Ei... Read more

A few years ago I was working on a circuit to cancel background signals in transcapacitive fingerprint sensors. Since fingerprints features are really tiny, the capacitances were too (on the order... Read more

Recently at work, I needed to determine the impact of removing some top-level power supply routing from a circuit. Out of curiosity, I decided to see if there was a way to have an expression for a... Read more

One of my favorite parts about UnRaid is the seamless ability to create virtual machines. I like to do most of my work on Linux and having a VM allows me to try different distros and easily manage... Read more

A few months back I converted my desktop into a home media server using UnRAID. The details for that deserve its own post, but suffice to say that one reason for going this route is to take back c... Read more

Recently I decided to mess around with my Home Assistant setup and accidentally borked my MySQL installation on my Raspberry Pi 3. Getting it up and running again was a bit of a pain, so I decide... Read more

I like knowing what’s happening on my home network, especially with how many things I have that I rely on (PiHole, Home-Assistant, etc). One thing I’ve been missing is the ability to check for unw... Read more

Why Jekyll? Before moving to Jekyll I had been using a Wordpress blog hosted on paid Namecheap servers. The thing is, my blog is pretty much entirely static so that set-up was mostly useless. Al... Read more

I’ve gotten a lot of feedback regarding my post last year outlining design using the Inversion Coefficient and figured it was time to outline how I go about designing a given circuit.  If you haven... Read more

One of the forums I attended this year at ISSCC 2016 was entitled “Advanced IC Design for Ultra Low-Noise Sensing”.  There were a variety of great speakers, but the presentation given by Professor ... Read more

Lately, I’ve been looking at harmonic distortion in circuits and was curious about the Total Harmonic Distortion, or THD, of a sine wave mixed with a square wave.  That got me thinking about the ma... Read more

I’ve previously covered the topic of noise in circuits and figured I’d elaborate even further. Many ICs use some sort of switched-capacitor circuit for SOME reason (sample-and-hold, for example) an... Read more

Building off of my previous posts Circuit Design Interview Questions: Part I and Part II, we’ll now explore the last set of questions that require some decent knowledge of frequency response charac... Read more

Building off of my previous post Circuit Design Interview Questions: Part I, we’ll now explore some slightly more advanced questions (still, they should be solvable by any EE graduate with some bas... Read more

We recently had a few co-ops come in for interviews and two of the guys I worked with needed to come up with some questions to ask. Neither them nor I had any experience on the other side of the ta... Read more

Continuing with the theme from my last post, I have some more neat noise analysis; this time looking at an Opamp. Most people would probably end up using this type of analysis rather than looking a... Read more

A really interesting topic in analog circuit design is noise analysis. Noise is everywhere and can be a pain to deal with. There are many types of noise, but the three most common are: Thermal ... Read more

For a recent class, our project was to design a 7-bit 5MSPS Current-Steering DAC in 0.5um technology. While the specifications aren’t neccesarily hard to meet, the time-table was rough. We had to g... Read more

For a recent class I was taking, entitled “Advanced Field-Effect Devices”, we were tasked with choosing a specific topic pertaining to MOSFET theory, performing an extensive literature search, and ... Read more

For my Analog Design class, each student was tasked with designing an OpAmp in 0.5um technology with the following specifications: Open-loop gain of at least 3000 V/V Unity-gain Bandwidth of ... Read more

I’ve been busy (understatement of the year).  I’ve been working on multiple projects (many of which will be highlighted here in the near future) and as the quarter is winding down, I figured I’d sh... Read more

The other day at work I found myself without much to do since I was waiting for some data analysis to be sent back to me.  I talked to another Engineer looking for some work I could do in the meant... Read more

So I have finally migrated most of my projects from SVN to Git.  My github page is located here and there is a link in the sidebar to the right.  I have a few old projects I put up there, as well a... Read more

After getting a few projects done today I had a bit a free time and for some reason remembered a story my Linear Systems professor told my class about a year ago.  Here’s the gist: he was listening... Read more

First of all, this post does not condone speeding.  Don’t do it, it’s stupid and puts other peoples lives in danger.  That said, there is a neat noise problem that may be able to get you out of a t... Read more

I came across a simple but interesting noise problem today dealing with the design of a matched filter. Matched filters, for those of you that may not know, are primarily used in communications sys... Read more

Boy have I been overwhelmed with work these past couple of weeks!  On top of all that course work I’ve had to fit in job interviews so my free time has been nearly non-existent.  Luckily it looks l... Read more

For a Computer Architecture class last year each student was tasked with designing a CPU with a given set of specifications.  My specs were: Indexed Memory Address Arithmetic Multiplexers (as... Read more