Circuit Breaker

Real circuit design stories — PCB failures, debugging sessions, and hard-won lessons from makers.

19 posts

What a Circuit Breaker Actually Is (and Why You Probably Need One)

Fuses and circuit breakers both interrupt current during a fault — but they work differently, fail differently, and suit different applications. Most makers reach for fuses by default. Here's when a circuit breaker makes more sense.

Circuit Breaker

Polyfuses Explained — The Resettable Fuse You Should Be Using

Polyfuses (PTC resettable fuses) are polymer-based fuses that trip under overcurrent and reset automatically when the fault clears. They're ideal for USB ports, small motor drives, and any application where you want basic protection without manual intervention.

Circuit Breaker

Protecting the Power Rail on ESP32 and Similar Boards

ESP32 boards are not particularly robust against power rail faults. Voltage spikes, reverse polarity, and overvoltage from a misconnected supply are common causes of dead boards. Basic protection is cheap and simple.

Circuit Breaker

Electronic Current Limiting vs. Fuses — When to Use Which

Electronic current limiting (via ICs or discrete circuits) gives you precise, adjustable protection that responds faster than any fuse. But fuses are still necessary in many systems. Understanding the difference helps you use both correctly.

Circuit Breaker

LiPo Battery Protection Circuits — What's Actually Required

Lithium polymer batteries require protection against overdischarge, overcharge, overcurrent, and short circuit. Most maker builds rely on the protection built into battery packs — but not all packs have it, and some applications need more.

Circuit Breaker

Fuse Selection for DC Robotics Power Systems

Fuses are simple in principle but selecting the right one requires understanding continuous current, inrush current, interrupt capacity, and the trip time curve. Getting it wrong is worse than not having one.

Circuit Breaker

Crowbar Circuits for Overvoltage Protection — When and Why

A crowbar circuit deliberately shorts the supply rail when overvoltage is detected, blowing the upstream fuse and disconnecting the load. It's the right choice when you need guaranteed protection regardless of how fast the fault develops.

Circuit Breaker

Reverse Polarity Protection — Four Methods Compared

Reverse polarity is one of the most common wiring mistakes in maker projects. Four different protection methods handle it differently. Which one is right depends on your voltage, current, and how much voltage drop you can tolerate.

Circuit Breaker

ESD Protection for Electronics — What Makers Actually Need to Know

ESD damage is often latent — the component doesn't fail immediately, but its performance degrades and it fails prematurely. Understanding where ESD matters and what protection looks like helps you avoid this class of invisible failures.

Showing 10–18 of 19 posts