PROTO216 is a concept of protoboard design based on ISO 216 standard. The purpose of this concept is providing an alternative to traditional breadboards for prototyping, and increasing compatibility with other standards like Arduino.

So what's the main differences with the rest of protoboard solutions in the market? Easy: following the ISO 216 standard for PCB sizes. This way PCB's can be stored and used with inexpensive commercial office products like folders, classifiers or even envelopes (like in the picture attached).

The board shown here is the A4 Breadboard, in which you can install modules up to DIN A9 size. This board has a very close A4 size (297 x 210mm), slightly reduced to 296.6 x 209.6mm due to manufacturing tolerances. All the rest of compatible boards are designed with smaller sizes like A6, A7, A8 or A9, keeping the original proportions. This philosophy makes this concept very easy to build and stack.

The A4 breadboard has two main sides: left and right. These sides have independent dual power rails 1 and 2, being 4 different power rails in total (VA1, VA2, VB1 and VB2). Rows from each side are interconnected, having a total of 4 connectors per row and 24 signal pins per connector. Up to 192 signals can be used in the A4 Breadboard, with the possibility of combining all of them in multiple ways, depending on the prototype needs.

All designed boards can be found in the GitHub repository here https://github.com/cararca3/PROTO216/