Mixed Signal Development
Build the Hardware. Understand the Design.
Sergio Luna
Founder & Electronics Engineer
Switzerland
The person behind MSD
Hi, I'm Sergio. I built this because I had to.
I'm an Electronics Engineer originally from Spain. In 2022 I moved to Switzerland to work as an R&D engineer at a biotech company — which is my day job. Mixed Signal Development is what I do with the time left over, because I genuinely can't stop thinking about circuits.
If I could have had kits like this when I was starting out, I would have learned twice as fast.
MSD started out of frustration with the PCB kits I kept buying. Bags of components, a barely readable schematic, and zero explanation of why the circuit worked. You'd solder it, power it up, watch the LED blink — and learn absolutely nothing. So I started designing my own, the way they should be made: real documentation, firmware you can actually read, and write-ups that explain the thinking behind every design choice.
This is a one-person side project built on evenings and weekends. It's not a startup, it's not a team — it's just me, genuinely obsessed with making mixed-signal electronics more accessible. If you have a question about a kit or a design, reach out. I actually read those emails.
— Sergio LunaR&D Engineer by day · MSD by night · Switzerland
How it started
I'm from Spain originally, but in 2022 I packed up and moved to Switzerland to work as an R&D engineer at a biotech company. New country, new lab, new challenges. Mixed Signal Development started as my way of staying connected to the electronics work I love outside of office hours.
The trigger was the PCB kits I kept buying for fun. Every one was the same disappointment: bag of parts, an unreadable schematic, no explanation of the circuit at all. I'd build them and walk away knowing nothing more than before. It worked. I learned nothing. So I started designing my own — the way they should have been made in the first place.
MSD is still a side project — evenings and weekends, squeezed around a full-time job. That's not a disclaimer, it's just the reality. Every kit I release has been designed, documented, and tested by me personally. No shortcuts, no filler. Just the kind of educational hardware I wish had existed when I was starting out.
Documentation that actually teaches
Every kit ships with the kind of explanation I wish I had when I started — schematics, component reasoning, design tradeoffs, and firmware you can actually read.
Real mixed-signal design
Not beginner toys, not unobtainable pro gear. Boards that live in the interesting middle ground — where analog meets digital and things get genuinely tricky.
Built by an engineer, for engineers
I review every design personally. If I wouldn't be proud to put my name on it, it doesn't ship. No filler products, no mystery chips, no missing documentation.
What sets this apart
01
Documentation that actually teaches
Every product includes detailed guides, schematics, and firmware so you understand what you're building — not just how to assemble it.
02
Accessible, no compromises
Professional-grade mixed-signal designs with full engineering documentation. Good electronics education shouldn't require a university lab.
03
Hands-on by design
Choose between preassembled boards or DIY kits. I believe the best way to learn is by doing — and making a few mistakes along the way.
04
Real mixed-signal circuits
From op-amp templates to the I2C Playground, everything I design lives in the interesting space where analog meets digital.
Documentation
See our documentation in action
Every MSD kit ships with a full engineering design guide. See what's inside and why it matters.
This is what I'm building
A place where you can buy a PCB kit and actually walk away understanding what it does. Not just a blinking LED — a real circuit with a real story behind every component choice.
If that sounds like the kind of electronics education you've been looking for, you're in the right place. Every product I ship is my way of saying: you deserve better than a bag of parts.
100%
Fully documented
DIY
Kits you actually learn from
1
Engineer who reads your emails