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Tantalum is a really misunderstood capacitor. Well, all capacitors are misunderstood, but that’s a subject for another post. I ran across this post on the Arduino forums on the Arduino GSM shield. In the post, ddewaele, reports that the shield blew up, catching fire. At first some might think it was due to abuse by the user. While it is possible that reversing the polarity or applying over-voltage could cause a catastrophic failure, it is also possible that the user doing nothing wrong could result in the same failure mode!

Wait, what? So what gives? Well, there’s two things to understand. First, Tantalum doesn’t explode. It takes almost 2000°C before Tantalum metal will ignite. Okay, so if Tantalum doesn’t explode what is ddawaele seeing? It’s the cathode material, Manganese Dioxide, (MnO2) that is exploding…

Regulator Types

Fundamentally there are two types of voltage regulators:  linear and switching.  The names come from how they operate and how they achieve voltage regulation.  Linear regulators tend to be a little cheaper to implement, but they aren’t as efficient as their more complex switching variants.

There are also some “cheap and dirty” methods that some designs use.  Below is a brief description and example of each.

Nearly every consumer device makes use of the Light Emitting Diode (LED). This highly versatile device offers an easy way to add an indicator to any project while drawing a relatively small amount of current. Once their operation is understood, adding them to any project is a simple task. This tutorial is a simplified explanation of how a LED works and how to select a current limiting resistor. The LED tutorial here is enough to use LEDs in a project but is not intended to be a thorough explanation.

LED Anode and Cathode