Voronoi Diagram Based PCB Lamp V2
Introduction: Voronoi Diagram Based PCB Lamp V2
Hey Everyone what's up.
So here's one of the previous projects I made a few weeks ago.
Voronoi Diagram-Based PCB Lamp is an RGB Lamp made entirely from PCBs, I used four rectangular PCBs with two square PCBs to make the body of the LAMP.
RGB Color in this Lamp can be changed by pressing the button on top of it, this button is connected with the lower square board that contains the RGB LEDs and the Attiny85 Microcontroller.
Supplies
* Attiny85 SOIC8
* Custom PCBs- Main Square MCU PCB and Rectangular PCB
* WS2812B LEDs (2020 Package)
* USB Type C Port
* Diode M7
* 2R0 Resistor 1206 Package
* Arduino as ISP Setup for flashing the MCU
* SMD button
* UC202 Connector and wire harness
* Solder wire
Step 1: PROBLEM IN PREVIOUS EDITION
Version 1 of this project had a few issues, including the wrong footprint issue for the RGB LED and the Gap Issue between two rectangular boards.
For solving the Gap Issue, I made the Square PCBs (Microcontroller board and switchboard) a little bit smaller than their previous version.
I decreased the square length by 1mm from all the sides in order to make the square PCB a bit smaller.
As for the RGB LED issue, I added SMD WS2812B 2020 Package LED on the top side of the PCB and that solved the RGB LED issue.
Step 2: PCB Design
This was the schematic I used in this build, it contains an Attiny85 connected with four RGB LEDs that are all powered by a USB Type C Port which has a Diode and a Load resistor in series to limit the output current.
After finalizing the schematic, I converted it into a board file and prepared two PCBs that were 1mm shorter from all sides.
The Length reduction thing was crucial as it controls the gap that occurs during the final soldering process of Side PCBs.
Step 3: PCBWAY REVIEW
After finalizing the PCBs, I send both PCBs to PCBWAY for samples.
I choose a white soldermask with Black Silkscreen and placed the order.
After waiting for a week, PCBs arrived and their quality was super good.
Overall, there was no error whatsoever and these PCBs that I made were complex.
Loved how each detail I made in this PCB was proper and perfect.
Check out PCBWAY for getting great PCB service for less cost!
Step 4: PCB ASSEMBLY PROCESS
PCB Assembly Process consists of five major steps that include
* Removing Conjoined PCBs
* Solder Paste Dispensing Process
* Pick & place process
* Hotplate reflow
* Switch and connector PCB assembly
Step 5: Removing Conjoined PCBs
While Designing the Square PCBs, I made two separate boards, one for microcontroller setup and one for the switch that also acts as a Lid of the Lamp.
If I made two PCBs and placed an order for them separately, that would've cost a lot so in order to save a few bucks, I connected two same-size square boards together with two RIBs that can be easily cut down to separate two PCBs.
This saves a lot of costs and it's a pretty neat method of combining two or more orders together, it's a kind of PCB Paneling.
Step 6: Solder Paste Dispensing Process
We apply solder paste with a solder paste dispenser syringe or the proper method is to use stencil here which I don't have. but anyway, after this, we can now move on to the next process, which is to add components to each pad.
Step 7: Pick & Place Process
Next, we carefully pick all the components with an ESD tweezer and place them in their assigned place one by one.
Step 8: Hotplate Reflow
Then after doing the pick and place process, we carefully lifted the whole PCB and place it on the hotplate. I’m using my good old DIY hotplate which I made a few months ago.
Basically, in this hotplate reflow process, the surface heats up to the solder paste melting temp and it slowly melts. after a few mins when the solder paste completely melts, we remove the PCB and let it cool down for a moment.
Step 9: Switch and Connector PCB Assembly
I then added SMD Button and UC202 connector manually with help of a soldering iron. 982