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Say "Hello" to the LogiSwitch Workbench

Clive Maxfield
|  Created: December 26, 2019  |  Updated: March 16, 2020

The LogiSwitch Arduino Uno Workbench Proto-Extender Kit (Image source:

As the Indian novelist Savi Sharma once said, "Everyone has a story." While this is undoubtably true (my mother certainly has lots of them), it's also true that some peoples' stories have more richness and complexity than others.

Take my chum, Mike Pelkey, for example. If you perform a Google Search on "BASE Jumping" -- that is, parachuting from a fixed structure, where BASE is an acronym for building, antenna, span (bridge), and earth (cliff) -- you will quickly find that the American freefall cinematographer Carl Ronald Boenish is considered to be the "father" of this sport. So, if Carl is the "father," who is the "grandfather"? Well, "Good golly Miss Molly," as they say, it's none other than Mike Pelkey who, with his friend Brian Schubert, made the first parachute jumps from the top of the El Capitan mountain in Yosemite National Park in 1966.

Throughout a 40-year career of designing digital systems, commencing circa the dawn of the microprocessor, Mike -- like every other design engineer on the planet -- was plagued by switch bounce problems. Having evaluated and employed every version of hardware-based and software-based switch bounce mitigation known to humankind, Mike decided that there had to be a better way, resulting in his founding LogiSwitch and bringing his LogiSwitch Debouncer ICs to the market.

But that's not what I wanted to talk to you about (don’t worry, I'll tell you more in a future column). Mike is one of those people whose brain is always buzzing with new ideas (I'm the same, except that my ideas typically turn out to be useless).

A few months ago, I was chatting to Mike on the phone and regaling him with details of my latest Arduino Uno-powered hobby project. As part of this, I was bemoaning the fact that I was using a couple of breadboards and I had a rat's nest of flying leads. The problem was that I kept on inadvertently pulling leads out of the Arduino or one of the breadboards, after which I spent way too much time trying to work out where they should go.

A few weeks later, a small package arrived at my office. You can only imagine my surprise to discover Mike's latest creation, which he dubbed The LogiSwitch Arduino Uno Workbench Proto-Extender Kit (he doesn’t like to restrict himself when it comes to naming things).

This really is a very cunning idea. What Mike's done is to create an Arduino Uno shield that extends out at either side and at the back. He's then routed the power (5V and 3V3) and ground pins, the six analog pins (A0 to A5), and the fourteen digital pins (D0 to D13) to the three extended sides.

The image below shows Mike's Workbench plugged into an Arduino Uno and with one side plugged into a breadboard. There's also a 2-row x 16-column LCD display plugged into the breadboard. If you've ever used one of these displays, you'll know that they typically require a bunch of flying leads, but there are no such leads in the image below.

"Look Ma; No flying leads!" (Image source: Mike Pelkey)

This might be a good time to mention the additional components on the Workbench. First, there's a reset switch in the upper left-hand corner of the above image. This performs the same function as the reset switch on the Arduino itself. At the bottom left of the board there are three LEDs with associated current-limiting resistors. The inputs to these LEDs are connected to a 3-pin header, thereby allowing you to connect them to any of the Arduino's pins. There are also three momentary tactile switches. These feed into a 3-channel LogiSwitch debouncer IC. The outputs from this IC are connected to a 3-pin header, once again allowing you to connect them to any of the Arduino's pins.

The reason these are called "Workbench Kits" is that you have to assemble them yourself. In fact, there are three such kits in the . First, we have the LS400-BB (bare board), which includes the Workbench board and the main headers. Meanwhile, the LS400-18 and LS400-118 kits come with all of the additional components, the only difference being the type of debouncer IC -- an LS18 or an LS118, respectively (I'll explain the differences between these families in a future column).

Things really become exciting when you see the Workbench plugged into three breadboards as illustrated in this video. On the right we see an Arduino Uno using flying leads to drive three breadboards, each carrying nine LEDs.


On the left, we see the equivalent circuit implemented using a LogiSwitch Workbench. In this case, there are only three flying leads, and these are used to implement breadboard-to-breadboard connections, not Arduino-to-breadboard connections.

I fear Mike has started to get carried away, because he just sent me the two images below. The first shows an Arduino Uno using flying leads to drive three breadboards, each carrying a 2-row x 16-column LCD display. The second image shows the same circuit implemented using a LogiSwitch Workbench. I think the results speak for themselves.

Arduino Uno using flying leads to drive three LCDs on three breadboards (Image source: Mike Pelkey)

Arduino Uno + LogiSwitch Workbench driving three LCDs on three breadboards (Image source: Mike Pelkey)

As one final example, I just used the LogiSwitch Workbench Mike sent me on my current project. This involves a test bench I'm using to evaluate different LED effects associated with toggle switches and potentiometers. In fact, I just posted this column that shows my own "before and after" pictures.

Even if you don’t use the Arduino Uno yourself, I bet you know someone who does, in which case they would probably be very happy if you were to share the good word by sending them a link to this column. In the meantime, I would love to hear your thoughts on this little rascal (the Workbench, not Mike Pelkey).

About Author

About Author

Clive "Max" Maxfield received his BSc in Control Engineering in 1980 from Sheffield Hallam University, England and began his career as a designer of central processing units (CPUs) for mainframe computers. Over the years, Max has designed everything from silicon chips to circuit boards and from brainwave amplifiers to steampunk Prognostication Engines (don't ask). He has also been at the forefront of Electronic Design Automation (EDA) for more than 30 years.

Well-known throughout the embedded, electronics, semiconductor, and EDA industries, Max has presented papers at numerous technical conferences around the world, including North and South America, Europe, India, China, Korea, and Taiwan. He has given keynote presentations at the PCB West conference in the USA and the FPGA Forum in Norway. He's also been invited to give guest lectures at several universities in the US and at Oslo University in Norway. In 2001, Max "shared the stage" at a conference in Hawaii with former Speaker of the House, "Newt" Gingrich.

Max is the author of a number of books, including Designus Maximus Unleashed (banned in Alabama), Bebop to the Boolean Boogie (An Unconventional Guide to Electronics), EDA: Where Electronics Begins, FPGAs: Instant Access, and How Computers Do Math.

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