Christian Lo's Tiny Mechanical Keyboard Costs Just $5 in Parts — and Makes a Perfect Giveaway
Built around an WCH Electronics CH522, this ultra-cheap keyboard was designed for use as swag — and an on-the-go text entry tool.
Software engineer and keyboard enthusiast Christian Lo has designed possibly the cheapest mechanical keyboard you could make without having to go dumpster-diving for parts: the idawgz32. a 32-key pocket-friendly keyboard built with just $5 in parts.
"A mechanical keyboard, in this economy? [The idawgz32 is] an experimental ultraportable and ultra-affordable pocket keyboard that costs $5 worth of materials to make," Lo explains of the design.
"I got excited with the new recent trend of building keyboards with the [WCH Electronics] CH552 chip, and wanted to expand on my pusheenz40 design, with the end goal of building a keyboard that costs so little that I can freely give it away as a small gift or as a freebie at conventions. The size of the board, layout, and component selection (or lack there of) are all in service of getting the price as low as possible."
That size is, perhaps, the biggest drawback of the idawgz32: despite using mechanical switches and boasting 32 keys in a split ergonomic ortholinear layout, the entire keyboard is roughly the same footprint as a credit card — making for an undeniably cramped typing experience better suited to twin-thumb use than touch-typing.
Getting the size down was only part of the project, though: each component has been picked for minimum cost, shaving the bill of materials down from Lo's earlier and similarly-sized pusheenz40 by moving to the ultra-low-cost WCH CH552T eight-bit microcontroller with integrated USB Device support. Other changes, Lo admits, may be more controversial — such as the removal of the transient voltage suppression (TVS) diode and fuse.
"One surprising realization that came out of the process was the discovery that the switches are by far the most dominant cost factor for any given mechanical keyboard, barring a fancy metal CNC'd case," Lo writes of his findings during the project. "Even for a 40 key STM32 board with a decent amount of trimmings, the keys took up the majority of the cost of a keyboard."
The experiment was derailed, sadly, due to a high failure rate in the G-Switch mechanical switches chosen for their low cost. "While these prototypes cannot be given away due to defects in the switches," Lo admits, "they helped confirm a lot of experimental questions I had. Primarily, they confirmed that a 32 key layout is viable for me, as well as validating that FAK [keyboard firmware] is usable for my current and future layouts."
The project is documented on Lo's blog, while the design files have been made available on GitHub under the reciprocal GNU General Public License 3; Lo advises, however, waiting for a 2.0 design that uses more reliable switches before building your own.