Give a man a fish and he has food for a day; teach him how to fish and you can get rid of him for the entire weekend.
—Zenna Schaffer
PatternAgents has just released a new library of MinnowBoard Lures (expansion board patterns) for the MinnowBoard project. The library includes Type A, B, and C Lures, with both single board patterns and "stackthru" patterns, which allow multiple Lures to be stacked up on top of each other. If you are thinking about designing your own set of Lures, then this is the place to start.
We've been interested in high performance small form factor platforms for a while now, especially those that can run Linux. The MinnowBoard is very high performance single board computer (SBC) using a 1Ghz Intel Atom processor, but unlike most SBC's it has the General Purpose I/O (GPIO) expansion connections needed to expand the system using low cost peripherals. The MinnowBoard runs the Angstrom Linux Distribution (as well as Debian) and is compatible with the Yocto project.
As you can see from the Expansion connector (on the left) in the picture of the MinnowBoard, the Expansion Boards, which are called "Lures", mount on the top of the board and stack upward.
The MinnowBoard specifies three different sizes of Lures, known as Type A, Type B, and Type C. The Type A Lure is the same size as the MinnowBoard itself, 4.2 by 4.2 inches. Of the three (3) types of Lures, the largest Type A, is larger than the "Free" version of Eagle supports, and requires a Standard or Professional license to work with. However Type B, and Types C both fall within the size restrictions of the "Free" versions of Eagle, and will be more popular within the general maker community.
We started looking at the resources available for designing our own Lures using Eagle, and found that only Type B and Type C were available for Eagle. We also found that there were only examples for single boards, and that none of the Libraries that we found supported "StackThru"; that is to say, none of the examples we found included a connector pattern on the top of the Lure in order to allow more than one Lure to be stacked at a time.
Since we had some ideas for more comprehensive Lures, we wanted both a Type A Lure pattern, as well as a Type A ST (StackThru) Lure pattern. So, we are proud to announce the availability of a more comprehensive MinnowBoard Lure library for Eagle, which has been released on our PatternAgents Eagle CAD Libraries Github Repo. We have included Type A, Type A ST, Type B, Type B ST, Type C, and Type C ST patterns for the MinnowBoard community to use.
Here is an quick example layout using the PatternAgents Type C ST (StackThru) board pattern,
rendered using Eagle, EagleUp, and SketchUp.
In the next article, we will cover an example Lure design using the PatternAgents Board Library for Eagle, and give a more detailed How-To on adding these boards to your projects.
Note Bene: When using the PatternAgents Boards Library for Eagle make sure that you use the PatternAgents.dru DRC control file for Eagle, as we have our minimum hole sizes set to 14mils. This makes the vias more like production vias, and also allows us to utilize 13.5mil magnet wire for fabricating manual vias when using two layer copper blanks (i.e. cut or milled PCB's) for testing. Or, if you have you own custom DRC file, than just set the minimum hole size to 14mils, to avoid getting any "Drill Size" DRC errors.
These libraries are updated frequently, and you should check for the latest version before generating your PCB's. Also note that some footprints are labeled "experimental" in these libraries, so be careful with those. You should always verify your design against the actual component footprints before fabrication by printing out a 1:1 plot.
For more information on Eagle, see CadSoft.
PatternAgents Eagle CAD Libraries - Files and Documentation
PatternAgents Eagle CAD Libraries - Contents
- PatternAgents-Boards.lbr - PatternAgents PCB board outlines, MinnowBoard Lures and other small form factors
- PatternAgents-Interfaces.lbr - PatternAgents Interface patterns for common interfaces
- PatternAgents-TouchWidgets.lbr - Capacitive Sensing Touch Widgets for Buttons, Sliders, Dials, etc.
- PatternAgents-Beautify.lbr - Page Outlines, Power/Gnd Symbols
- PatternAgents-Logos.lbr - Logos for RoHs, ESD, etc.
- PatternAgents-Cypress.lbr - Components from Cypress Semiconductor
- PatternAgents-NXP.lbr - Components from NXP (nee Philips)
- PatternAgents-TI-Tiva.lbr - Components from Texas Instruments
EagleCad Libraries by PatternAgents, LLC are available and licensed under a
Creative Commons Attribution-ShareAlike 4.0 International License.
The MinnowBoard on Google+
About PatternAgents
PatternAgents provides community and commerce for electronics designers, helping them to collaborate using shared patterns, practices, and resources; connect with others in the industry, conceptualize and create new ideas, commercialize their designs, and keep up on the latest technologies and concepts.