Sunday September 24, 2017, I will host the 2nd live stream of AddOhms. My first live stream was a test for the technology pieces. I’ve made some refinements and am giving it a second try. For that reason, I’m keeping the topic really simple.
The Agenda for the Live Stream is:
News (3 stories or projects that I found interesting)
Op Amps with the XL741
Whatever surprises pop-up.
In the livestream, I’ll be talking about inverting and non-inverting circuits using an op-amp. But I am not going to use just ANY op-amp. I’ll be using the MASSIVE XL741! (I did a review of Evil Mad Scientist Lab’s XL741 in the past.)
In this video, I discuss considerations for SSD Capacitors, with a focus on enterprise applications. (No, not the ship kind, the business kind.) As more consumer devices use solid state technology, it gets easier for us to forget the importance of keeping data safe during storage. While solid state drives are more robust than their spinning counterpart, they are not perfect. Just like with spinning drives, there is a small delay from when a write occurs until the data is stored permanently. The highest performance solid state drives parallelize data in a way to minimize this propagation time. However, these drives also keep an active copy of the allocation table in RAM.
Just like the RAM in a PC, when power is lost, so are the contents. So it is critical for a solid state drive to have a reserve bank of energy to dump the RAM contents into permanent storage. Modern drives use huge banks of capacitors to write out any RAM buffers when the system’s rail voltage suddenly disappears.
The first part of the tutorial looks inside of a Brushless DC Motor, or, BLDC. Then I show a discrete transistor circuit that can drive one. Of course, you’ll need a Microcontroller like an Arduino to drive it! Lastly, I briefly talk about an ESC.
Overall, a BLDC is better than a Brushed DC Motor (talked about those on #20) because:
Supplyframe Hardware has published a video of a talk I gave in July 2017. This talk was at HDDG 22. The focus of my discussion was how an oscilloscope’s trigger circuit works. I built on that and talked about some of the behind-the-scenes stuff of what is going on with a digital oscilloscope. (You can download my HDDG 22 slides here.)
During #22 of the Hardware Developers Didactic Galactic meetup, I discussed Oscilloscopes. (Previously James talked about capacitors.) In the presentation, I broke down the internals of an oscilloscope. The presentation started off with a block diagram. Then I discussed the main components: vertical amplifier, A/D, memory controller, some of the computer side stuff, and the keynote was on triggering.
The trigger circuit of an oscilloscope fascinated me since very early in my HP/Agilent career. When I saw trigger modes like Pulse, Violation, Rise Time, and “Runt,” I thought: Wow, this must be the most complicated circuit in the scope! While it isn’t trivial, it very clever how just a few pieces of (relatively) simple hardware drive one of the most important aspects of a digital scope.
Rick Altherr also gave an excellent talk on ECUs and their sensors. (I always thought ECU only meant engine control unit. His talk helped me understand why that isn’t really the case anymore!) It was great to learn about the combination of the engine mechanics with the electronics that control it. !)
Oscilloscopes belong on the desk of every electrical engineer or hobbyist. They are invaluable in both debugging and characterizing a circuit. While most users can twist the knobs to make things show up on screen, most never fully understand what is happening behind the scenes. Having spent over a decade working at a couple of scope companies, I have unique insight into how these incredible machines actually work.
If you have any interest in retro computing or technology, The 8-Bit Guy is one of the best YouTube Channels. His latest video hits a little closer to home. He shows how to Character LCDs work and how to hook them up. He always does a great job with his videos, so I encourage you to check out some of his others.
When I made the AddOhms Tutorial on Linear Regulators, I made a comment about the 7805. I said it may be one of the most important Integrated Circuits (ICs) ever made. That’s a bold statement. The 555, 805, or 7400 might all qualify for such a distinction. My feeling about the 7805’s importance is because it is a chip that is still popular today. It is used, or at least was used, in so many applications. And it is the heart of many 5V digital systems.
Including the Nintendo Super Famicom (and I assume the US SuperNES).
This picture is from an SFC I disassembled to repurpose the case. While taking it apart, the 7805 caught my attention because it was attached to a shield as a heat sink. Also, I find it fascinating that it is one of 3 or 4 through-hole components on the entire system. As you can see from the picture, it needs some cleaning. I might post more pictures later.
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.
There are a few other neat tricks and some slow-motion stuff too. Near the end, he compresses a quarter with the scariest magnet setup I’ve ever seen. This video is definitely worth watching if you like anything related to Tesla coils–or electricity!