There are a lot of little details you need to think about when taking a project from PoC (proof-of-concept) to production. Most projects today have some form of onboard microprocessor and require you to flash your custom bootloader and/or program code onto it at some point. There are many ways this can be accomplished but the most common method is using an ICP (in-circuit programmer) connected to a 6-pin ICP header somewhere on the PCB. One of the cons of this method is that the actual 6-pin header costs money (around $.11 each) and takes up valuable board space. It’s also a through-hole part which could add to the assembler cost if you populate the header. That said, most often in large production runs you don’t need to populate the header and there is typically expensive programming test/jig’s with pogo pins that mate with the header holes to program the microprocessor. That’s not the norm with small to medium production runs and still doesn’t solve the issue of valuable board space.
Tag-Connect! I can’t remember exactly how I found out about this neat little connector, but I’ve been using it for a while and it’s actually very useful in a production environment. They provide the footprint for many of the popular PCB design programs so placing it is very straight forward. Pretty much just swap out the traditional header for the new tiny Tag-Connect version and you’re pretty much done.
HOW IT WORKS
There are many different flavors of tag-connect available depending on the type of device you’re programming but if you are designing Atmel AVR (Arduino) projects with an AVRISP you’ll probably either need the TC2030-IDC-10 or the TC2030-IDC-NL-10.
The differences between the two is simple — one has “legs” that clip while the other does not. I prefer the “NL” or no-leg version as it’s quicker in a production environment whereas the legged version clips into position which is better for PoC or debugging. The legged version does take up more space. There is a retaining clip available for use with the non-legged version great for when needing to debug a production board.
The innovative part is that the connector itself has the pogo-pins and three rigid guide pins that make alignment and mating simple and quick — zero friction.
The only cost involved with using Tag-Connect is just the programming cable price which runs about $34 (no royalties or fees) that’s not bad considering all the pros you get from using this connector. Installation is simple, just pop open your AVRISP and replace the only cable with the new one. I’ve been very happy with the performance and results. Programming my production file (.elf) onto the boards only takes about 10 seconds. All you need to do is apply power to the board and then press fit the Tag-Connect connector to the board and press program on the AVR programmer software. Very fast and easy.