In 1971, Texas Instruments released something no one else had ever seen before. The TIL305 was an alphanumeric display, powered by LEDs. Sure, the technology of the early 70s meant the LEDs weren’t very bright, and the displays were expensive, but if you want a display that’s simply classic, and relatively low-power, you won’t be able to do better than a vintage alphanumeric LED display.
As you would expect, new old stock TIL305s are still pricey, and now everybody has access to cheap PCB manufacturing capabilities and really small LEDs. The DIYTIL305 is an attempt to replicate the vintage stuff, and it looks great.
The vintage, TI-made TIL305 is a printed circuit board that clips into a DIP-14 socket. The LED array is 5×7 pixels, with an extra dot for a decimal point, set on a 0.05″ grid, and a translucent red diffuser. A PCB is easy, and with 0201 LEDs you can get the LED pitch you need. Turning a PCB into a DIP-14 only requires a few machine pin headers, and for the diffuser, this project is using laser cut cast acrylic. It’s simple if you have a pick and place machine or a steady hand, and assembly is a snap.
The final DIYTIL305 boards are being tested right now, but so far the results are great. With the right code on a microcontroller, these displays will blink through the digits 0 through 9, and the alphabet is just a little more code. Since this project is using 0201 LEDs, it also means green, white, blue, orange, and yellow displays are possible, something no one could have dreamed of in 1971.