The last step in building a new electronics project is to solder all the components onto a circuit board. You can use something as simple as a perf board or you can go all out and etch your own custom circuit board. Whatever you use, you need to figure out how the parts will be arranged on the board.
There are a number of programs that you can download to help you design a circuit board layout (examples: 123D, EAGLE Light and PCB Artist). But you can also use everyday programs such as photo editors that you might already have on your computer. So today I am going to show you a simple way that you can use programs like Photoshop to design a circuit board layout.
Step 1: Materials
Here are the materials and tools that you will need for this project
Large Perf Board
Circuit components needed to build your circuit
Photo editing software such as Photoshop
Step 2: Set Up Your Circuit Board to Be Photographed
The first thing that you need to do is set up your circuit board to be photographed. You want to have a plain background such as a sheet of white paper. Set up your camera on a tripod and position it directly over the paper.
Take the piece of perf board and set it on the center of the paper. Now find something that is one to two inches tall to prop up each side of the perf board. I used a pair of 2x4 boards. By propping up the perf board we can insert electrical components into the holes and the leads of the components can hang below the board without getting in the way.
Step 3: Photograph the Board and Components
The next step is to photograph the board and the components. You want the picture to be taken straight down. So position the camera directly over the board and point the camera down.
Now insert all of your electrical components into the board. Try to keep them spaced out so that there is blank space between each one. This will make them easier to select in the photo editing program.
Some components such as resistors and diodes can be mounted in more than one configuration (flat against the board and standing on one end). So you may want to have one in each orientation.
Once all the parts are in place, take a picture of the board. You want the picture to be as zoomed in as much as possible to capture the most detail. Then firmly hold the board in place and remove each of the components. Try to keep it in exactly the same place. Then take a second picture of the blank board. The picture of empty board will be used as a background. The picture with the components will be separated into individual images of each part.
Step 4: Open the Pictures in Your Favorite Photo Editing Program
Open up the two picture files in your favorite photo editing program. I am using Photoshop elements 13.
Step 5: Combine the Two Images
Now you need to combine the two images. Start by rotating the images so that the edges of the circuit boards are lined up vertically and horizontally. To do this, open up the "Image" menu and select "Rotate." Then select "Custom" to enter in the exact amount to rotate the image. This will take some trial and error to get the images lined up perfectly.
Once both images are properly aligned, you need to overlay them. Copy the image with the parts and Paste it as a new layer onto the image of the blank board. Now the two images are on different layers of the same file.
On the layer with the parts, set the "Opacity" to 50%. This will make it partially transparent so that you can faintly see both images. Move the top layer so that the boards on both layers are lined up` directly on top of each other. Then set the "Opacity" back to 100%.
Step 6: Separate the Individual Parts Into Separate Layers
Use the selection tool to select individual parts. Try to include some of the surrounding holes in the selection. This will make it easier to line them up later. Copy and paste each of the individual parts into separate layers. Rename each of the layers to describe what each part is.
In order to know how each part will be connected to the others, you will need to know where the terminals/leads are. So on any part where the terminals are not visible from the top view, you may need to add a colored dots to indicate where the terminals are. These can be added to the layer of the part or made as a separate layer and linked to the part layer.
Make the layer with the combined parts invisible. Make sure that the layer with the blank board is the bottom most layer or the background. All the parts that are now visible should be on separate layers that can be moved around independently. By having the blank circuit board visible behind all the other parts, you can effectively move them around on the board. This lets you arrange and rearrange the components to find the best configuration.
Step 7: Arrange the Parts on the Board
Now you need to find the best configuration for all of the parts. Start with the parts that have the most connections. In this case, that is the 555 timer IC. Place this in the center of the board. Start adding parts around it. Try to minimize the distance between terminals/leads that will be connected together.
When moving the parts around, inevitably some of the images will overlap. When this happens, you can use the "Eraser" tool to remove part of the top image so that both parts will be visible.
Step 8: Add Connections Between the Parts
Now we need to mark where the connections will be. Create a new layer on top of all the others. This will be the connections layer.
To show where the connections will be, use the "Selection" tool to select the area between the terminals that will be connected. Then use the "Fill" tool to fill in this area with a solid color. By setting the "Opacity" of the connections layer to 50% or less, you will make the connection lines transparent and you will still be able to see any parts that they are overlapping.
To view just the connections layer, make all the part layers invisible. This will show you just where the connections will be.
Step 9: Etch a Custom Circuit Board (optional)
Now that you know where the connections need to be, you can use this to etch your own custom circuit board. This step is optional. For most circuits, it is just as easy to use a perf board and make the connections with a bead of solder.
If you want to make a custom circuit board, here is a good tutorial by Instructables use Ohm.
And here is another method illustrated by Collin Cunningham from Make Magazine:
Step 10: Solder the Circuit Together
Now that you have worked out where all the connections need to be, you are ready to solder the parts together on the board.
The connections map that you created can help in this step as well. You can use it as a reference to check your solder connections. However, you need to keep in mind that the image that you made will be the mirror image of the connections on the bottom of the board. If you want, you can correct this in your photo editing program. Just select the connection on the connections layer. Then "Mirror" it horizontally or "Transform" it by setting the width with to -100%. This will give you a map of the connections from the perspective of the bottom side of the board where you will be soldering.