Comprehensive Home PCB Fabrication Tutorial

December 19, 2012 by Mike Szczys 15 Comments

home-pcb-fabrication

From what we’ve seen we’d say [Jianyi Liu] is really good at etching PCBs at home. Now you can learn from his experience. He just published a mammoth guide to fabricating your own PCBs at home. That link goes to his index page which leads to all eight parts of the guide.

He starts off by mentioning that fab house boards are rather inexpensive these days. This will save you a lot of trouble (like acquiring the equipment and raw materials needed to get up and running) but you can’t beat the turnaround time of doing it yourself.

After discussing the particulars about trace width, copper thickness, and a few design considerations he lays out his board and prints the artwork to a sheet of transparency film. A pre-sensitized board is cut to size before a trip through an exposure rig with the film taped onto it. The image above shows him rinsing the board after applying the developer chemical. From here he uses cupric chloride he mixed himself to etch the board. [Jianyi] recommends populating the components before cutting the panel apart — a task which he accomplishes with a hack saw.

Automated PCB Panelization

December 17, 2012 by Brian Benchoff 13 Comments

panel

Some PCB production houses – Seeed Studio and itead studio, especially – allow you to upload a gerber file and receive a printed circuit board very inexpensively. The pricing structure for these board houses is based on predesignated board sizes – 5cm square or 5×10 cm – and sometimes a project is just too small to justify buying a full 25 square centimeters of board. This is where panelizing comes in: by putting multiple copies of a circuit board on one of the available sizes you can get more boards for the same amount of money. But how to panelize your boards without the (sometimes) hassle of cutting and pasting?

[Martin] came up with a way of panelizing PCBs with just a Python script. By creating one copy of a circuit board in KiCAD, he can fire up his script and tell the computer exactly how to duplicate his circuit to fit any size board.

By his own admission, [Martin]’s script is still a little clunky, but it does allow him to edit the panelized board in KiCAD and also copies the nets so the ratsnest doesn’t go between boards.

Level Converters To Make All Your Hardware (5.5V And Under) Play With Each Other

December 11, 2012 by Mike Szczys 18 Comments

txb0108-level-converters-ks0108-stellaris-launchpad

I finally set aside some time for one of my own projects. I have been playing around with ARM microcontrollers a lot lately and wanted to try out my GLCD display that uses the KS0108 protocol. It’s 5V but I had heard that some of these displays will work with 3.3V TTL. But the datasheet tells me otherwise. I tried using a pull-up resistor to 5V and configuring the Stellaris Launchpad pins to open drain, but the low voltage wasn’t getting below the 0.3V threshold needed by my display. My only choice was to use some type of level conversion. I actually ended up driving the KS0108 using a pair of TXB0108 level converters.

I figured this had to have been done before so I check over at Sparkfun. Their offerings are either one-way or have a direction pin that you must drive yourself. I figured there had to be a bi-directional solution and a search over at Mouser led me to the TXB0108. It is exactly what I was looking for and as you can see I etched my own circuit boards to make the TSSOP chips breadboard compatible. I’ve documented the process you can find the code and board files at my post linked above.

Update: one of the Reddit comments mentions this chip is available on a breakout board from Adafruit if you’re interested.

Through Hole Plating And Milling At Home

November 29, 2012 by Mike Szczys 27 Comments

Here’s a PCB fabrication process that makes us envious. It’s pretty darn close to fab-house quality at home. [Cpirius] is using a CNC mill and through hole plating technique to produce his double-sided circuit boards.

The video embedded after the break shows one board from start to finish. It begins with the mill drilling holes through some double-sided copper clad stock. Once the millings have been cleaned off the holes are coated with a mixture of waterproof ink and carbon. This prepares them for plating by making the holes themselves conductive. The board is then run through an electroplating process based on this guide.

Possibly the most interesting part of the process starts 52 seconds into the clip. The mill uses a conductive probe to generate a height map of the entire board. This allows it to vary the routing depth for perfectly cut isolation traces. That final routing process is pictured above.

Continue reading “Through Hole Plating And Milling At Home” →

MSP430 Launchpad Game Of Life Shield

November 19, 2012 by Mike Szczys 2 Comments

[100uf] built an LED matrix shield for the MSP430 launchpad. His goal with this design was to have it play Conway’s Game of Life. It does just that, as you can see in the clip after the break. But it’s just waiting to learn some more tricks. After he tires of watching the cellular automaton he can try his hand at making some LED pendant animations.

As you can tell, the board was made in his home workshop. It’s not etched, but milled using the CNC machine shown in this image gallery. This is a single-sided PCB, which works well enough for the surface mount components and the downward facing pin sockets. But we wonder how difficult it was to solder the legs of that 8×8 LED matrix. It does have plastic feet at each corner that serve as standoffs to separate the body from the copper layer. But it still looks like a tight space into which he needed to get his iron and some solder.

Continue reading “MSP430 Launchpad Game Of Life Shield” →

Upverter 2.0 Launches

November 6, 2012 by Eric Evenchick 41 Comments

Disclosure: I currently work at Upverter

We’ve featured Upverter here in the past. At that time, the EDA tool was capable of collaborative schematic capture. Today, Upverter is launching version 2.0 of their tool which includes many new features allowing for end-to-end electronics design.

Upverter now has a PCB editor, allowing you to manufacture your designs. They are working with PCB manufacturers to make it easy to choose a fab and submit design files. Other new features include a Spice based simulation engine allowing in-browser simulation, and product lifecycle management features to help manage your project’s bill of materials.

When we last looked at Upverter, it was just a tool for creating and sharing schematics. With today’s launch, the tool can be used for designing electronics from start to finish. Since Upverter is free for open source projects, it will be interesting to see how hackers use it.

You can check out a tour of the new features. Any thoughts on using a cloud based EDA tool? Let us know in the comments.

Semi-professional Board Assembly For Your Workshop

October 29, 2012 by Mike Szczys 10 Comments

[Zach Hoeken] has the answer to assembling multiple surface mount PCBs in the home workshop. It’s certainly not for everyone. But if you’ve ever thought of marketing your own small runs he has the equipment and methodology you need.

He had tried using hacked together equipment, but after encountering a range of issues he finds the investment in a few key items saves time and money in the long run. The first is a precision tooling fixture block; that metal plate with a grid of holes that makes up the background of the image above. It comes with machined pegs which fit the holes perfectly, and as you can see, his panel of 16 boards include tooling holes that line up with the fixture. Once in place, a steel solder stencil is aligned with the board using its own tooling holes. The alignment of the stencil and its uniformed thickness ensure that the perfect amount of solder paste is easy to apply with a squeegee. [Zach] hand places his components but he did invest in a proper reflow oven to make the soldering a set and forget process.