Temple T
My Story of the Temple T
This project was initially started a few days before graduation. I was enjoying a few drinks with my good friend Alex and thought it'd be a good idea to slap a new LEDs on my cap. The next day I layed out a fast a dirty design with 70 RGB LEDs. The design used only surface mount components since drilling through holes was too difficult to align. This design lacked any bypass capacitors, which eventually became an issue. The processor used was a ATMEGA328P, which was socketed. The pins on the socket were bent flat so that it could be soldered flat on the board. The board was soldered on a disgusting frying pan on which my and my roommates cooked all of our meals (Don't worry, lead free solder and components were used). Two wire jumpers were used to allow the board to be a single layer PCB.
After graduation, I was unemployed and want to feel better about myself. So I began to order PCBs for a couple of my best friends and former professors. These boards had more switches and buttons to control the pattern, brightness and color settings. Operating this device was overly complicated, just look at the instructions below.
2019 Experience Temple Day
After adding up how much money I spent on these Ts, I wanted to design something more cost effective. I reduced the board size down to 10cm, and changed the MCU to a ATTINY85. My idea was to make a board that could be used at Temple's annual soldering event. After the soldering event, Dr Li Bai asked me to make a few boards for Experience Temple Day. Experience Temple occurs 4 times a year, and is an opportunity for high school students to explore Temple's engineering program.
Dr Bai had received on my original larger RGB T's, and wanted the cost reduced Ts to have more features. So i begun to redesign the board. This board contains 40 LEDs and runs off of 2 CR2032 coin cell batteries. The biggest issue of this board is the battery life which greatly depends on brightness and mode. I hand assembled over 40 of these boards for Experience Temple Day. An additional 50 units were ordered from an assembly house.
Tinier T
Li Bai then requested a smaller T to wear to social events. The size of the board was reduced to a quarter of the size and the IC's packages were changed. The size of the chips became so small that a microscope was needed for assembly. Luckily, I had a co-worker kind enough to give me one. The 74HC595's below are a 16-VFQFN package with a 0.5mm pitch.
2019 SolderSoldering Event
For the 2019 Temple IEEE soldering event, the through hole Tiny T was revised. Pads of the components were increased to make soldering easier. The number of LEDs was also decreased to 32. About 35 students attended. They assembled either a snow flake, Christmas tree, or tiny t.
I'm working on providing my source files.
