Tag Archives: ProtoSpring

  • ProtoSpring, part 3: manufacturing and demo

After coming up with the idea in part 1 for ProtoSpring, the prototyping board for Springboard,  and creating the PCB in part 2, this final segment shows the end-result and a demo application – using GPIO to control a 7-segment display from an Android app!

Finished Prototyping Board

After finishing the v1 of the PCB, I’ve exported the Gerber files from KiCad and sent them to Seeed Studio. Looking at their specifications, some of the filenames they require were different from the ones KiCad creates by default (the board outline and the drill files need different extensions). It’s a bit weird,  but it’s easy enough to adjust before submission.

The board fits on a 5 cm x 10 cm base, has 2 layers, standard 1.6mm thickness, and didn’t bother changing the PCB colour to save some money on the manufacturing (though I bet the others looks very good too). The printing took less than a week together with shipping from Shenzhen to Taipei, and got 5 boards for about US$20:

ProtoSpring board straight from manufacturing

The board feels really nice and solid, and I’m almost surprised that it worked out so well on the first try (this is my first ever PCB!) After reviewing it, I’ve added a few changes for future print runs: Continue reading 

This entry was posted in Springboard Blog and tagged ProtoSpringprototypingelectronicsAndroid on November 7, 2014 by Gergely Imreh.

  • ProtoSpring, part 2: schematic revision and PCB

In the first part of this series I’ve outlined the idea of making a prototyping extension board for the Springboard, and finished with a rough schematic. Since then I’ve revised the schematic based on experience, and laid out the prototyping board PCB.  By the end of this write-up we’ll have a complete design, ready to send to manufacturing.

Before I dive in, probably the single most important lesson learned is to keep in mind all different stages of a board design. There’s a lot of back and forth between schematic, components, footprint, layout, manufacturing specs. The tools help making the right decisions, and often when something feels difficult it is because I’m doing it wrong…

Finding crucial parts

After making the basic schematic I realized that there’s one type of component on the board that can make or break the entire project: the board-to-board connectors. To interface with the Springboard needed to find 2mm pitch, dual row, through hole, perpendicular mounting female receptacles. I couldn’t find anything like that in the local electronic stores. After an hour of search online they did turn up, fortunately both Digikey and Mouser had the required 3×24×2, and 7×2 connectors by 3M.

Finally found the correct 2mm, double row, perpendicular, through-hole connectors I needed

I got a bit lucky too, because these ones can be ordered piecemeal, while other pin count versions (e.g. the 10×2) require minimum order of 300 pieces. This is one of the first example of the importance of choosing components. Of course, if these were 0.1″ (2.54mm) connectors then there wasn’t any problem finding them in the first place, but then they would probably not fit on the Springboard itself… Continue reading 

This entry was posted in Springboard Blog and tagged ProtoSpringPCBschematicKiCaddesignelectronics on October 28, 2014by Gergely Imreh.

  • ProtoSpring, part 1: Idea and Schematic

I was looking for a project to showcase how easy it is to extend the functionality of the Springboard platform, drawing inspiration from the expansion board that is bundled in the kit.

Springboard and expansion board (top), from klinger.net

The expansion board connects to the main board with a couple of pin headers (power, GPIO, sound) and cables (USB) to break out some of the functionality to easy to access connectors, such as the regular speaker and mic plugs, two USB, on-off button. It should be easy to replace that board with another to provide different functionality, so I’ve come up with an example. Continue reading