An Amazing DIY Single Board ARM Computer With BGA

July 11, 2014 by Nick Conn 37 Comments

DIY Single Board Computer ARM

Typically, you buy a single board Linux computer. [Henrik] had a better idea, build his own ARM based single board computer! How did he do it? By not being scared of ball grid array (BGA) ARM processors.

Everyone loves the Raspberry Pi and Beagle Board, but what is the fun in buying something that you can build? We have a hunch that most of our readers stay clear of BGA chips, and for good reason. Arguably, one of the most important aspects of [Henrik’s] post is that you can easily solder BGAs with cheaply available tools. OSH Park provides the inexpensive high-quality PCBs, OSH Stencils provides the inexpensive stencils, and any toaster oven allows you to solder even the most difficult of components. Not only does he go over the PCB build, he also discusses the bootloader, u-boot, and how to get Linux running.

Everything worked out very well for [Henrik]. It’s a good thing too, cause we sure wouldn’t want to debug a PCB as complicated as this one. What projects have you built that use a BGA? Let us know how it went!

Extending EagleCAD With Python

June 30, 2014 by Brian Benchoff 45 Comments

eagle Although it’s derided for not being open source, EagleCAD is an extremely popular piece of schematic and PCB layout software. Most of the popularity is probably due to the incredible amount of part libraries – it’s certainly not the features Eagle has to offer or its horrible scripting capabilities. [Rob] had enough of the lack of good scripting support in Eagle, so he’s been spending his time making Eagle’s ULP work with Python. He’s only been at it a short time, but already it’s much more usable than the usual Eagle scripts.

Below you can check out a pair of videos of [Rob]’s Python tools for Eagle in action. The first video goes through aligning a few symbols and creating a board outline (with proper curves!) from a DXF file. The second video shows exactly how valuable these tools are when laying out a board: imagine hundreds of LEDs and resistors automatically aligned to each other with a single click of a mouse. Beautiful.

All the PyEagle stuff is available on [Rob]’s github, with a DXF importer, group manager, and alignment tool included. Now that everything’s Python, it’s easy to build your own tools without relying on Eagle’s odd ULP language.

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Handheld Game System Powered By Arduino

June 22, 2014 by Rick Osgood 16 Comments

DIY Handheld Game System

These days, it’s easy enough to play games on the go. If you have a smart phone, you are pretty much set. That doesn’t mean you can’t still have fun designing and building your own portable gaming system, though.

[randrews] did just that. He started out by purchasing a small memory LCD display from Adafruit. The screen he chose is low power as far as screens go, so it would be a good fit for this project. After testing the screen with a quick demo program, it was time to start designing the circuit board.

[randrews] used Eagle to design the circuit. He hand routed all of the traces to avoid any weird issues that the auto router can sometimes cause. He made an efficient use of the space on the board by mounting the screen over top of the ATMega chip and the other supporting components. The screen is designed to plug in and out of the socket, this way it can be removed to get to the chip. [randrews] needs to be able to reach the chip in order to reprogram it for different games.

Once the board design was finished, [randrews] used his Shapeoko CNC mill to cut it out of a copper clad board. He warns that you need to be careful doing this, since breathing fiberglass dust is detrimental to living a long and healthy life. Once the board was milled out, [randrews] used a small Dremel drill press to drill all of the holes.

The final piece of the puzzle was to figure out the power situation. [randrews] designed a second smaller PCB for this. The power board holds two 3V coin cell batteries. The Arduino expects 5V, so [randrews] had to use a voltage regulator. This power board also contains the power switch for the whole system.

The power board was milled and populated. Then it was time to do some measurements. [randrews] measured the current draw and calculates that he should be able to get around 15 hours of play time using the two 3V coin cell batteries. Not bad considering the size.

[via Reddit]

One-Off Kapton Solder Masks

June 22, 2014 by Brian Benchoff 16 Comments

soldermask

With the proliferation of desktop routers, and a number of easy methods to create PCBs at home, there’s no reason anyone should ever have to buy a pre-made breakout board ever again. The traditional techniques only give you a copper layer, however, and if you want a somewhat more durable PCB, you’ll have figure out some way to create a solder mask on your homebrew PCBs. [Chris] figured Kapton tape would make a reasonable soldermask, and documented the process of creating one with a laser cutter over on the Projects site.

The solder mask itself is cut from a piece of Kapton tape, something that should be found in any reasonably well-stocked tinkerer’s toolbox. The software for [Chris]’ laser cutter, a Universal Laser Systems model, already has a setting for mylar film that came in handy for the Kapton tape,

Of course, getting the correct shapes and dimensions for the laser to cut required a bit of fooling around in Eagle and Corel Draw. The area the laser should cut was taken from the tCream and tStop layers in Eagle with a 1 mil pullback from the edges of the pads. This was exported to an .EPS file, opened in Corel Draw, and turned into a line art drawing for the laser cutter.

The result is a fast and easy solder mask that should be very durable. While it’s probably not as durable as the UV curing paints used in real PCBs, Kapton will be more than sufficient for a few prototypes before spinning a real board.

OpenExposer, The DIY SLA Printer

May 28, 2014 by Brian Benchoff 25 Comments

printer

Precisely applied ultraviolet light is an amazing thing. You can expose PCBs, print 3D objects, and even make a laser light show. Over on the Projects site, [Mario] is building a machine that does all of these things. It’s called the OpenExposer, and even if it doesn’t win the Hackaday Prize, it’s a great example of how far you can go with some salvaged electronics and a 3D printer.

The basic plan of the OpenExposer is a 3D printer with a small slit cut into the bed, and a build platform that moves in the Z axis. The bed contains a small UV laser and a polygon mirror ripped from a dead tree laser printer. By moving the bed in the Y direction, [Mario] shoot his laser anywhere on an XY plane. Put a tank filled with UV curing resin on the bed, and he has an SLA printer. Put a mounting bracket on the bed, and double-sided PCBs are a cinch.

The frame is made of 3D printed parts and standard RepRap rods, with the only hard to source component being the polygonal mirror. These can be sourced from scrounged laser printers, but there’s probably some company in China that will sell them bulk. The age of cheap SLA printers is dawning, friends. Video below, github here.

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Adding Copper Wire To A 3D Print

May 25, 2014 by Brian Benchoff 24 Comments

Conductive filaments and printing solder are one thing, but what if you could spice up your 3D prints by embedding wire right inside the filament? That’s what [Bas] is doing, paving the way for printable electronics, PCBs, coils, and odd-shaped antenna.

The general idea of [Bas]’ technique of embedding thin copper wire inside a single layer of a print is to lay the wire down in front of the nozzle, effectively turning bare wire into insulated wire in whatever shape you can imagine. The trick, however, is figuring out how to put wire down in front of a nozzle. [Baz] accomplished this with a slew ring turned by a stepper motor connected to a 5th axis on the control board.

There are a few things this prototype doesn’t cover – cutting the wire, connecting the wire to components, fine-tuning, and a host of other things that prevent [Bas]’ machine from building real functional circuits. Despite these limitations, the machine could probably fabricate the secondary for a tesla coil right now, something that’s really annoying to make unless you have a lathe.

Video demo below.

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Custom Nixie Tube PSU Is A Lesson In Good PCB Design

May 11, 2014 by Rick Osgood 25 Comments

Nixie HVPSU

[Jan Rychter] was sick and tired of not being able to find the right power supply for his Nixie tube projects, so he decided to design his own. [Jan] started out designing around the MAX1771 (PDF) DC-DC controller, but quickly discovered he was having stability problems. Even after seven board revisions, he was still experiencing uncontrolled behavior. He ended up abandoning the MAX1171 and switching to the Texas Instruments TPS40210. After three more board designs, he finally has something that works for him. [Jan] admits that his design is likely not perfect (could have fooled us!), but he wanted to release it to the world as Open-Source Hardware to give back to the community.

The end result of [Jan’s] hard work is a 5cm x 5cm board that generates four separate output voltages from a single 12V source. These include both a 3.3V and 5V output for digital logic as well as a 220V out put for Nixie tubes and a 440V maximum output for dekatrons. The circuit also features several safety features including over-current protection, thermal shutdown, and slow-start. Be sure to check out [Jan’s] webpage to view out the schematics and technical information for this awesome circuit.

Need some Nixie tubes to go with that circuit? We know some resources for you to check out. Or you could always just build your own. How can you use this board in your next project?