Hey Guys, so this is my RGB Glasses Project which has 49 WS2812B SMD LED soldered on the front frame. this post includes the soldering process of SMD LEDs on Frame PCB with an SMD Hotplate and a custom Stencil.
Also, this is all controlled by an sparkfun's Pro Micro but the future version will have an ESP12F Embedded on the Temple of glasses with a small Li-Po Battery.Glasses Analogy
The normal Eye Glasses Consists of these general parts which are the RIM or Frame, Temple, Bridge, Lenses, etc.
the Important structure of Glasses is its Frame and Temple and my goal is to make a PCB Frame so I took some reference from the Normal/Average design of glasses and made its outline in my CAD Software (OrCad Cadence).
Also, I took a little Design input from this image of Kanye West and added SMD LEDs to it without altering its shape too much.
- WS2812B RGB LEDs x49
- 100nf x5
- Custom PCB (which was provided by JLCPCB)
- Pro micro (for controlling the RGB LEDs)
- SMT HOTPLATE
- Custom Stencil (Provided by JLCPCB 👌👌)
- Solder Paste
Thanks, JLCPCB for providing PCB and stencil for this project, you can check them out from here if you want High-Quality PCB service for a low cost. www.jlcpcb.com
Here's the Schematic of the RGB Frame
Working of WS2812B SMD RGB is pretty simple, It uses Din Pin for receiving Signal from an MCU and changes its color according to that signal.
For Connecting multiple LEDs in a matrix or in a sequence, we need to connect each LED to VCC and GND, then connect the first LEDs Dout to the second LED's Din. the second LED's Dout goes to the Din of the third LED, and so on.Assembly.
So the goal here is to solder 49 SMD LEDs on the PCB. now, Most of the SMD Components can be soldered by a Soldering Iron with a fine tip but these SMD RGBs are not exactly soldering iron friendly. (it can be soldered by a soldering iron but it's not recommended to use a Soldering iron with these fragile LEDs)
one way of soldering these LEDs is to use an SMD Hotplate or reflow. a Hotplate is basically a device whose surface can heat up to a certain temperature which can be then used to melt the solder paste and mount SMD Components on the PCB. These HOTPLATES are available in a huge variety (but it can also be made with a Cloth Iron)
also, you can use an SMD HOT Blower Station here but it can damage the LEDs from overheat as the SMD Blower Blows heat from the top side which can melt the plastic housing/body of SMD LEDs so I prefer HOTPLATE over HOT BLOWER.
Anyway, I set up the stencil for the PCB by first placing the PCB on a Cardboard and matching the Component PAD of the PCB with the Stencil. when the PADs matched, I placed tape on both sides to hold the stencil steadily on top of the PCB and bring out an OLD Plastic Card for applying solder paste on the stencil.
(you can watch the video for a better video guide for this step)
I applied the Solder paste on the stencil with the plastic card evenly on each pad and the result was great as expected.
Now we need to pick and place each LED on PCB one by one in proper pin order.
also, you need to place them in the right order or your setup won't work properly, after placing all the LEDs on the PCB like a Pro, we can now place this setup on the SMD Hotplate and start the reflow process.
The result will look something like this-
After soldering the LEDs, it's time to connect this setup with an Arduino Board and upload some sweet test code to light this setup up.
and for that, ill be using an Arduino Pro Micro. so we need to wire the VCC of our glasses with RAW of Pro Micro, GND to GND, and Din to D3.
For uploading the code, we first need to download and install these two libraries which are
The installing process is well documented in the library docs.
we need to download them and then extract them in the library folder in the Arduino folder in Document.
Now open Arduino IDE and goto the example>FastLED>ColorPalette and change the number of LEDs to 49 and LED Pin to 3.
(or use my attached Sketch)
aaaand Hit Upload.
For now, I'm waiting for the TEMPLE PCB which has ESP12F Setup for controlling the Glasses. I designed the temple and frame in such a way that the temple will go directly in the slot given in the Frame PCB and we can then solder the VCC, GND, and Din pad with the temple.
and that is it for now.
will post part 2 soon so for now ciao!
leave a comment if you need any help or I did something wrong.