As an alternate you can always order your boards from OSHPark.com
Soldering iron (generic)
Story
1. Designing
I began by designing my circuit board in Patchr.io. I started by creating my snowflake shape, I researched inspirational images online and kept in mind that I would be supplementing with LEDs.
Before we begin, a few helpful shortcuts for Patchr:
Command + Z = undo
Command + S = save
Command + P = part view/pad view
Use the curved arrow button to rotate parts
1. Draw your board outline
For the perfect snowflake, take note of your segment lengths to help create symmetry.
Here is the completed board outline. If you need to, select a point to drag it to your desired location.
2. Placing Components
Once your board outline is complete, it is time to place components. The circuit itself is pretty basic, I am using an ATtiny85 and controlling LEDs through the PWM outputs on the chip. This will allow the LEDs to flicker, giving a shimmering effect. For our snowflake we used 16 LEDs but you can use as many as you see fit.
Select the ATtiny85 from the MCU part library and place it on your board
Navigate to the PWR part library on the right and place the battery clip
In order to be sure this project doesn’t constantly drain electricity, I placed a switch on the board, which can be found in the I/O part library
Drag and drop LEDs and place where you desire, feel free to delete the resistors that are automatically placed with the LED, to do this, select the part you want to delete and hit the "delete" key on your keyboard
All components are placed and board is ready to be routed
3. Routing Your Snowflake
Switch to pad view (command+p) and route your parts
Board fully routed and ready to be exported
4. Exporting
Select export and choose your preferred export method. If you have access to a Bantam Tools mill you can start printing your board today! Otherwise, I like ordering my boards from OSHPark.com.
Export options are available under File - Export
If you are using a Bantam Tools, I suggest rotating your snowflake by 45 degrees so it fits better.
Assembling the Snowflake
Gather your parts and materials
Insert the LEDs, double check you are inserting them with the anode & cathode in the proper location.
Solder the LEDs onto the board & repeat until all LEDs are connected.
After all LEDs are soldered, it's time to add the battery clip.
Add a bit of solder to the center square, and another little bit to the right square to secure the clip.
I use electrical tape to insulate the battery from bridging any of the routes below it.
Heat the right square, insert the clip into the molten solder, then move to add solder to the left square.
The switch will be added to the back of the board for easy on/off access.
I use painters tape to hold the component in place while I solder the other side.
Adding the ATtiny85:
The final step is to add the ATtiny85
Before we solder the ATtiny85 we need to bootload the chip. High-Low Tech has a great resource for bootloading the ATtiny (http://highlowtech.org/?p=1695), all you need is an Arduino Uno, some jumper cables, and a 10uF capacitor. I am also planning to upload a tutorial on how to do this, including some PCB shortcuts to use in bootloading.
Once it has been bootloaded, we need to add code to flicker the LEDs, I've attached the proper code below. You should use the same setup as with bootloading to add the software to the ATtiny.
Final soldering of ATtiny85
Insert battery, switch on and voila!
Finished Snowflake!
I will be sharing a future tutorial for using a vinyl cutter on home created PCBs.
Back and front view, time to hang them on the tree!
I’d love to see your snowflakes - please add any comments, questions or suggestions.
//PCB SNOWFLAKE Flicker
//MCU: ATtiny85
//By: Eric Schneider 2018int ledPWM1=0;int ledPWM2=1;int ledPin1=2;int ledPin2=3;void setup(){ pinMode(ledPin1, OUTPUT); //set the pin mode to output
pinMode(ledPin2, OUTPUT); pinMode(ledPWM1, OUTPUT); pinMode(ledPWM1, OUTPUT); digitalWrite(ledPin1, HIGH); //turn on the first 2 sets of LEDs
digitalWrite(ledPin2, HIGH);}void loop(){ analogWrite(ledPWM1, random(120)+50); //randomly flicker the LEDs
analogWrite(ledPWM2, random(120)+50); delay(random(100)); //delay this loop at a random value from 0 to 100}
Comments