For a university project I started working on RGB LED Shutter glasses, which are based on the idea of a kickstarter by Macetech. However, these glasses miss some features I was looking for and therefore seemed a good idea to improve upon. Also, they are pretty expensive and most components were given by my university so I was very glad my idea was chosen for the project. That said, our project goal was pretty simple: reverse engineer these glasses and make them react to sound.
However, during the project I stumbled on some pretty cool other use cases for these glasses and therefore decided to develop it further in my free time. However, our prototype is very rough. The LED's are on a pcb which is taped on some 3d glasses and a four threaded wire is connecting the LED pcb to the microcontroller. Not quite nice looking...
Since I want to use these glasses for myself (and wearing them at festivals), I want to make them look more professional. So I'm planning to create a 3D design which is bulkier than normal glasses but doesn't look stupidly big. This means all my electronics (except power) must fit in a small case in the glasses itself. For that, the legs of the glasses seem the best idea, especially if only one leg is used. This volume is approx. 4x6x1 cm.
The electrical components for in the glasses' legs are:
- Wemos D1 mini pro
- 3 buttons and a pull down resistor for each button
- Small microphone (max4465)
- Connector for power (located at the end of the legs of the glasses, so not in the said dimensions)
- Power delivery circuit (constant 5V, max 5A)
Therefore I'm looking for a way to get quite a lot of power to these glasses. The WS2812B I'm using has a max current of 60mA per LED, of which I have 72 which accounts for 4.32A. Normally these leds function on 5V, but they also seem to do fine on a bit less (li-ion voltage of 3.7-4.2V). So in the worst case they can suck 21.6W. Later on, I'm also planning on increasing to more leds while still maintaining the same surface. So for that I will be using the sk6812 mini, which I'm able to squeeze 100 leds on a new verion of the pcb. This will account for 50mA per led, which is at peak 25W.
Since I like to reuse the whole power design, I'm looking for a way to get constant 5V, max 5A. The way which seemed the most ideal to me was using a powerbank which has quick charge. To trigger this I could use a qc trigger board (as suggested here) and then step the voltage down to the desired 5V 5A. However these two boards are pretty large and certainly won't fit in my glasses.
I also found it's pretty simple to trigger qc, but since I don't want to waste power pulling a constant 12V doesn't seem like a good idea.
Last thing was that I saw a usb c qc trigger board on aliexpress, but these boards are very expensive.
So I'm interested, how I can efficiently pull power from a QC power bank and step it down to a constant 5V and a max 5A, while maintaining a small size?
I'm looking for a small circuit which can trigger QC and convert it to a constant 5V and a peak of 5A. How can I achieve this? Also, other options are welcome as well.
Earlier on, I said that I wanted more features from my LED glasses and will tell here more about that.
My glasses are currently able to display approx. 30 cool presets, but I have quite a lot of others in the making. Some of these presets have quite a lot of customizability, like setting a color (or on some a palette), showing different forms or reacting to sound or not. I also can show text and adress a certain letter with a color. And last but not least, it sort of works with ARTNET (recieves data, atm doesn't tell it's an ARTNET device). Also, I like to make an app which can control a certain preset and configure all the different options of it.