If I were a professional actor, I would feel typecast at this point in my career. Whenever someone wants to talk about Arduino, Oscilloscopes or Capacitors, they call me! In this case, element14 asked me to do two videos on how to replace multilayer ceramic capacitors (MLCCs) with Polymers.
Polymers are an interesting capacitor type. What is usually called a “polymer” is better a called a “polymer electrolytic.” The reason for that detail is the word “polymer” describes the cathode layer and not the dielectric.
For more details, why not check out this episode of element14 Presents’ The Learning Circuit! If you have questions about these capacitors, head over to element14 and leave me a comment there.
What are aluminum polymer capacitors? These are a solid type of capacitor that replaces the liquid electrolyte with a solid polymer material. Sometimes you might hear these capacitors called “organic aluminum.” Technically, they are still “electrolytic” capacitors. However, the colloquial term of “aluminum electrolytic” refers to the traditional wet electrolyte-based capacitors.
For me, the release of this video is bittersweet. It is one of my last projects before my departure from KEMET. However, I am excited to talk about aluminum polymer capacitors because they represent one of the “newer” technologies when it comes to capacitors.
Difference between Aluminum Polymer Capacitors and Aluminum Electrolytics
As mentioned, the key difference between the capacitor types is the electrolyte. In a traditional aluminum electrolytic, there is an electrolyte that connects the cathode plate of the capacitor to the cathode electrode. In a polymer capacitor, a solid conductive polymer material replaces the wet electrolyte. The most common polymer material is PEDOT. The use of this material provides an exceptionally low ESR which makes the capacitors can handle more ripple current. Also, because there is no electrolyte to “dry up” or “wear out,” the operational lifetime of these capacitors is much longer. Overall, aluminum polymer capacitors are an excellent alternative to traditional electrolytics.
Can you use voltage dividers as regulators? What if you add a Zener Diode? In this AddOhms episode, I show what happens when you try to power a complex circuit like an ESP8266 with a voltage divider instead of a regulator. (Spoiler: Get a voltage regulator.) This video tutorial is related to a write up I did recently on Zener Diodes. For questions or comments visit the AddOhms Discussion Forum.
Behind the scenes
A significant change for this AddOhms Episode is that I moved from Final Cut Pro X to Premiere Pro. I also shot the entire video in 4K, even though the output is 1080p. Animations were still done as 1080p compositions. One snag I ran into, the color corrections I applied in PPro, didn’t seem to get exported. You might notice when the breadboard is on screen, it has a very slight yellow tint to it.
I’ve been changing how I produce the videos. It’s shortening the cycle time. The key is that I’m not trying to animate every scene. The amount of work involved is just too much. I animate practically every frame. So in a 6-minute video, that’s just too much.
By the way, there are two easter eggs in this episode. Can you find them?
The Zener diode is often used to create a reference voltage. In tutorials and even college texts, there are mentions of creating a Zener diode based regulator. The idea is that the Zener maintains a known voltage drop. The problem is that current matters. This post looks a quick Zener diode overview and shows what happened when I tried to power a microcontroller using a “Zener diode regulator.”
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It is commonly known that ceramic capacitors change capacitance with applied voltage. What isn’t always as well known is how strong this effect can be and why it occurs. At KEMET we’ve put together a technical video that answers that question.
What is Ask An FAE?
Ask An FAE is a new video series we launched at my day job, KEMET. An FAE is a field application engineer. These engineers are very common in the electronics industry. Companies like KEMET, where I work, have FAEs who meet with customers to answer technical (and very detailed) questions about how to use their products. In UBM’s Mind of an Engineer survey, FAEs were ranked as one of the top information sources for design engineers.
At KEMET we decide to use FAEs to answer the questions. While I’m not an FAE today, I was in the past and happy to kick off the series with our CEO.
A switching voltage regulator is one of my favorite circuits. In school, they were the first circuits I built where I understood how transistors worked. In fact, they were the first circuit I saw an inductor being useful! Switching regulators are incredibly efficient when designed properly. Of course, this detail about design is important. They are not as simple as a linear regulator, which is basically an IC and two caps.
To understand the basics of a switching regulator, I released AddOhms #18 this week. This is video tutorial dedicated the Switching Voltage Regulator. If video tutorials aren’t your thing, then keep reading for my written tutorial.
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Hardware Developers Didactic Galactic is a group for hardware designers, hackers, and enthusiast to discuss hardware-related topics. HDDG11 (or 0xb) featured a presentation from SnapEDA CEO on Footprints and my presentation on Capacitors.
Titled “They’re JUST capacitors?” I used content from my time as a KEMET Field Application Engineer.
In the presentation I address the common myth or guideline: “capacitors should be derated 50%.” Comparing Aluminum, Ceramic, and Tantalum we discuss why each technology has a de-rating associated with it. Turns out, they all have different reasons to de-rate.
Additionally I give a brief introduction to Supercapacitors. (You’ll note that it is spelled with one word…) The key to understanding what makes them “super” relies on how they achieve the common capacitor structure of electrode plate, dielectric, electrode plate.
Whether you are an engineer with enough experience to be called a graybeard or a novice that keeps grabbing the wrong end of a soldering iron, there is one component that eludes everyone working in electronics.
It’s the humble capacitor.
A seemingly simple device, turns out, to be incredibly complex. While the basic electrode-dielectric-electrode structure sounds simple, the materials used in that structure drastically changes the characteristics of the device.