TechnologyThe BestieIntermediate
Designing Electronic Systems, a free technology course on Tomo

Designing Electronic Systems

Bridge the gap between simple breadboard circuits and robust, functional hardware systems. Learn how to condition analog signals, manage power and switching loads, coordinate noisy digital communication, and track down real-world hardware bugs.

Like Duolingo, but for Designing Electronic Systems. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.

24 levels across 4 sections, about 48 minutes end to end, roughly 10 days at five minutes a day. It moves through Making Signals Useful, Power and Actuation in the Real World, System Coordination and Control, and Diagnostics and Electrical Robustness. It assumes you already know the basics.

24 bite-size levelsAbout 5 minutes each

Free forever · No credit card · iPhone & Android

Sparky the Squirrel, the guide who teaches the Designing Electronic Systems course
Designing Electronic Systems
with Sparky the Squirrel
24
Levels
4
Sections
5
Min/day
What you'll learn

Key ideas in Designing Electronic Systems

  • A divider's lower branch forms a parallel circuit with the downstream device's input impedance.
  • Input impedance sags the output voltage unless it is at least 10 times the divider's resistance.
  • High-impedance inputs need op-amp buffers or lower divider resistances to measure accurately.
  • Standard 5V TTL inputs register any voltage above 2.0V as a valid logic HIGH.
  • Direct 3.3V outputs can drive 5V TTL inputs, but 5V outputs can damage 3.3V CMOS inputs without shifters.
  • 5V CMOS inputs require roughly 3.5V for HIGH, making level translation mandatory in that direction.
  • Schmitt triggers use separate upper and lower thresholds (hysteresis) to prevent signal chatter.
  • Level shifters safely translate signal voltages across incompatible power domains.
  • Internal pull-ups bias high-impedance inputs to a known rail when left unconnected.
  • CMOS inputs have gigohm-scale gate resistance and act like tiny, sensitive antennas when open.
  • Floating inputs pick up stray capacitive coupling and toggle unpredictably between 0 and 1.
  • Mechanical contacts physically bounce for 2 to 20 ms, generating multiple rapid edge transitions.
  • An RC filter slows switch voltage transitions to smooth out contact chatter before logic stages.
  • Software debouncing ignores repeated state changes during an initial settling delay window.
  • Negative feedback drives the op-amp output so the difference between input pins stays at zero
  • A grounded non-inverting terminal creates a virtual ground of 0V at the inverting pin
Why not just Google it

You've tried the other tabs

Wikipedia

Thirty open tabs. Four facts you actually kept.

YouTube

You watched. You nodded. By Sunday it was gone.

ChatGPT

One answer, then back to scrolling.

Online courses

Eight weeks. You meant to finish. You didn't.

Tomo gives Designing Electronic Systems the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.

Try a question

Here's what playing it feels like

A real question from this course. Take your best guess.

Hooking Up Sensors and Logic

To prevent your divider's output voltage from sagging, how high should the downstream input impedance be compared to the divider's resistance?

Get it right to open this lesson and 23 more in the app.

Course map

How to learn Designing Electronic Systems, step by step

Go in order. 24 short levels across 4 sections, about 48 minutes in all, five minutes a day.

  1. 1

    Making Signals Useful

    • Interfacing Sensors to Logic
    • Conditioning Analog Signals with Op-Amps
  2. 2

    Power and Actuation in the Real World

    • Switching and Driving Heavy Loads
    • Delivering Clean Power
  3. 3

    System Coordination and Control

    • Reliable Inter-System Communication
    • Feedback and Closed-Loop Control
  4. 4

    Diagnostics and Electrical Robustness

    • Systematic Diagnosis with Test Gear
    • Noise, Grounding, and Physical Protection

4 sections · 8 units · 24 levels. Built to play, not to enroll.

Questions

Questions about Designing Electronic Systems

  1. How do I learn Designing Electronic Systems?

    Go in order: start with Making Signals Useful, then Power and Actuation in the Real World, then System Coordination and Control, then Diagnostics and Electrical Robustness. On Tomo that's 24 short levels, about 48 minutes in all, played five minutes a day. Start free and play the first level in under a minute.

  2. Is there a Duolingo-style app for Designing Electronic Systems?

    Yes. Tomo works like Duolingo: short daily lessons, streaks and quick quizzes. Designing Electronic Systems is one of its free courses, and you can type any other topic to get a course of your own.

  3. Is the Designing Electronic Systems course free?

    Yes. Designing Electronic Systems is playable on Tomo's free plan, which doesn't expire. No credit card, no waitlist. Download the app and start your first lesson.

  4. How long does it take to learn Designing Electronic Systems?

    24 levels across 4 sections, about 48 minutes of play in total. It's built for five minutes a day, so you finish it a little at a time instead of all at once.

  5. Do I need any background to start Designing Electronic Systems?

    No. It's pitched at an intermediate level, so it starts where you are and builds up. If you can tap a phone, you can start.

New

Tomo is in ChatGPT

Tomo is also a ChatGPT plugin: the same playable courses, built and played inside your chat.

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How it's taught

You pick the voice

This course
The Bestie

Designing Electronic Systems is taught in the Bestie style: your friend who just gets it. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.

Keep going

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Start free

Start Designing Electronic Systems today.

Download Tomo, search Designing Electronic Systems, and play your first lesson in under a minute.