Wristwatch projects are coll for many reasons. First of all how they are built – components need to be squeezed to make watch wearable. Another thing is display. What different types of displays can be used. LCDs and LEDs seems to be getting boring, unless they are used in some weird way. Other things also are important like overall look, power supply , features and controls. Johnengineer has been working on steampunk wristwatch for couple months and he came up with something awesome.
The unique idea was to use IVL2-7/5 VFD display. They are relatively small to fit on a watch and pulls out relatively small amount of current. It also requires low grid voltage (~12V). Display is transparent, so background PCB is visible and this can be considered a cool design feature. Clock is ticking around Atmega88 microcontroller along with RTC DS3231. Display is driven by dedicated MAX6920 12-bit shift register. Since watch is powered from single AA battery, there are couple boost converters – one for generating 5V to power electronics and another 13.5V to power VFD grid. While designing circuit there are future options included like phototransistor, barometric/temperature sensor and accelerometer. The construction of watch definitely falls in steampunk category as there are brass and leather decorative elements.