Introduction: DIY Wireless Phone Charger & LED Control
In this instructable I will demonstrate how to make a Wireless Phone Charger and activated LEDs .. I will include code ,PDFs ,Wiring diagrams and Gerber files as well as a Bill of materials to make your own wireless phone charger.
Special note : Not all phones have wireless charging capability ..I had to buy a special adapter for my iPhone SE to be able to use this feature $19 From Amazon but totally worth it
Link is Here
Wikipedia defines Resonant Inductive Coupling as “the near field wireless transmission of energy between two coils that are tuned to resonate at the same frequency.”
The formula for calculating the resonant frequency is:
ƒr = 1/(2*pi*√(LC))
You can use a meter to determine inductance, but not for the distributed capacitance that accumulates between windings. You can use the following formula to determine the self-capacitance or the interwinding capacitance:
C = .29L + 0.41R + 1.94[ √ (R^3/L) ]
C = Self capacitance in picofarads
R = Radius of coil in inches
L = Length of coil in inches
The prototype coil for this project was purchased from Digikey.com as was the rest of the electronics..I had the PCB manufactured by PCBway.com they are cheap and fast in delivering my prototypes..I went with a pre built Prototype Charging station as the Home built coil units are complex and require more knowledge than the average DIY hobbyist but we are going to add a voltage and current circuit to wirelessly transmit Charging data to an external source.
Step 1: Micro Controller Board
The Micro Controller board can be modified to Hold any micro controller you want to hold the Fritizig Program has many Examples of different controllers. I prefer the Particle as it is extremely low cost and has wireless built in and external programming.
Step 2: Wireless Charging Unit
The Data Sheet for this is Here ..
The Website to buy is here ...
I know you can make your own Transmitter / Receiver units but for the purposes of this Demonstration I figured I could make it a little easier to build for the novice and hobbyist in us all. The DIY charging circuitry is very complex and would take a medium to expert builder to make properly and not ruin your phone tablet or cause a fire ....
This Instructable can be made by anyone with a soldering iron and a drill.
I purchased this charging unit for my IPhone from Amazon ..I wasn’t sure if it was going to work but it does ..I have now purchased another one for my IPad...And am going to make another one for it ...
Step 3: The BOX Where the Charger Will Be Installed
I seem to have a lot of these white boxes around but they are great for projects ..They have ample room but are low profile and seem to fit every project I have made to date ..I was going to use a Jewelry Box I had made but the wood was too thick to get a good charge. you can order these boxes from Digikey.com or Digikey.ca depending if your In Canada or the United States .. pretty sure digikey has offices all around the globe ..the link is here
Step 4: Building the Box Circuits
The Key to building a successful..project is to think it out ...get your supplies in place ..Have a good plan but be flexible ..I was going to use a Jewelry Box with hidden compartments but the wood was too thick for a good transmission of power ..Soooo I went with my White Box ..Have 5 or 6 laying around and they are great ..I found a great power plug at digikey which can be found here
I drilled a hole for the Power plug ..By chance I had a plug in transformer that fit perfectly..It’s output is 12 Volts 2 Amps which is perfect and can be found here ..
I used a big glob of silicon and glued the charging unit to the lid of the box and let it dry ..I tested the charging unit BEFORE I glued it.. I then drilled a hole big enough for the charging plug I offset it so I could tuck the power Metering PCB in tight to the Back side of the box..
I then Stuck a colourful sticker to the box to indicate where the charging base is. To Step it up a notch I added 3 rows of LED's Some Powered off the particle outputs, Some powered off the 12VDC power input. They are used as charging indication and also nice nightlights for the bedside table ..Glowing nicely when the Phone is on the Cradle.
Step 5: LED Installation
There is a picture of an LED for reference as to which pin is negative and which one is positive..( Very handy if you forget )..I started by finding a drill bit just large enough to be able to Insert the Led into the hole without it going all the way through ..Then I marked the box where I wanted to put the LEDs. Then I carefully drilled out all the holes and siliconed the LEDs in place ... Next day after everything has dried I started to solder the wiring and jumpers..Please see pictures..for the steps ..Ensure you don’t cross leads and if they are close you can use heat shrink to separate the leads so you don’t get a short circuit ...
The Following Code Shares do different things
Step 6: Soldering the New Boards
There are two techniques being used here for soldering ..I will demonstrate . the soldering iron work. The link for the solder is here
I bought a good soldering iron from Amazon and the link is here
Basics are simple take your time and have a hot soldering iron
Step 7: Installing the Board
Care must be taken when installing board ..Once everything is soldered and ready to go plug in your power and METER the connections to ensure you have gotten everything right .. if you mess up it’s ok ..Just fix it and move on ..If you have to order new boards it’s ok they are only $1.. each
Step 8: The Program
The link to the code is below .You can change the way that he “LED’s”tun on and off by adjusting the ms delays and triggers
After you copy/paste the code into your own sketch .Flash it and open the Particle app..the Particle app can be found either in The play store or the App Store.. the link is below ..Its hard to find so just click the link
Step 9: Testing the Program
Once you have the Program Flashed and the Particle app installed .. now this is the fun part .
When you open the particle device ..Mine is called charge_sensor
You will see a line called Data click on it and you will see one line called Function
Click on it and type in a 1 then enter ..You LEDs should turn and off a couple of LED's..Your LED's Should start flashing and producing interesting light show ..You can change the program all you want to get interesting effects
Step 10: The Final Product
Step 11: Fritzing Program Files
These files are opened with the fritizing program you can download and install from here