123D Circuits.io is a site where you can design circuits and PCBs in your browser for free.
This instructable will guide you through all the steps of creating and ordering a PCB.
Step 1: Getting Started: Creating an Account
First you have to create an account at https://123d.circuits.io You can also use Facebook or Twitter to log in.
Step 2: Creating a New Circuit
On your dashboard, click "New Circuit".
Step 3: Creating a New Project
Enter a name for your project, select the type of project (choose schematic circuit for this design), and click "Create new".
Step 4: Circuit Design: the Sidebar
Step 5: Circuit Design: Adding Components
To add common components, you can drag them from the left sidebar. If you need more advanced components, click on the "Search Component" button. Here you'll be able to search for other components. You can append an asterisk (*) to search with prefix wildcards, for example "74HC*".
Another example, if you want to add a screw terminal, search for "connector" and choose one.
Step 6: Circuit Design: Component Value
You can give your components a value by clicking on it and filling in the detail in the inspector appearing at the bottom of the screen.
Step 7: Circuit Design: Connecting Everything
To connect two points with each other:
- hover with your cursor over the component and click on the red square denoting a component terminal,
- click the other point in the schematic you want to connect it to (this can be either an existing wire or a terminal)
Step 8: Circuit Design: Using Labels
If your schematic is getting more complicated, you can keep it clean by using labels. The schematic on the 3 following screenshots is logically the same.
Step 9: PCB Design
Now that he schematic is complete we can start designing the PCB. This process is often called "laying out a board" or simply "layout" since it involves laying copper traces on the PCB.
Click in the menubar on the left to go to the PCB design.
Step 10: PCB Design: Sidebar
Step 11: PCB Design: Footprints
By default all the footprints are small surface mount components (SMD). If you want to change the footprint to through hole or any other package, select the component and choose the a different footprint in the pop-up menu.
Step 12: PCB Design: Placing Your Components Apart
Place your components such that not too many green lines cross and the design will be easily routable.
Step 13: PCB Design: Routing the Paths
The green lines, all together called a "ratsnest", and individually called "air wires" denote the electrical connections that you need to convert to copper traces. These come from the schematic design you made earlier.
Switch to the routing tool and click a pad to get started. Route the trace by moving your mouse and clicking at intermediate points until you reach the other side of the airwire. Make sure not to cross or come too close to other lines. The tool will show a warning when you make a mistake.
If you're stuck you can switch your trace to the other layer by pressing "L" on the keyboard or change the layer in the select box.
In the screen shot, you can see that for last connection I could:
- Rearrange my components or paths.
- Route the wire on the other side of the board, which is much easier. Double layer boards are standard on 123D Circuits.io and don't cost extra when ordered. The blue traces are on the bottom side of the PCB.
Step 14: PCB Design: Adding Polygons
To add a ground plane:
- click on the polygon tool
- click on a wire or pin you want the ground plane to be electrically connected to
- draw a polygon around your components
The polygon tool will be auto-computed to not be connected to any net except the one you originally connected with. Note that the copper pour is auto updated when moving components. Regions where the copper could not be electrically connected will not be filled with copper to avoid "floating copper" which can lead to interference.
Step 15: PCB Design: Reshape Your PCB
You can change the borders of your pcb by clicking on the pink lines around your PCB. You can drag the lines themselves, or click on a blue handles and move them separately. Double-clicking the outline will create a new handle to allow for more complex shapes. When you double clicking a handle, you turn the point into a B-Spline controlled point, allowing crazy bend shapes.
Step 16: PCB Design: Add Milling Holes
You could add some mounting holes using the drill tool. To change their diameter select it and change the diameter in the pop-up box.
Step 17: Project Page
If you're done with layout you can now go to the project page by clicking on the name of your circuit. Your circuit layout will auto-save.
Step 18: Project Overview
When all the traces are routed go back to the project overview and click "Mark as done". Now the design will show up in the gallery and other people can see it. It is now also possible to order the board.
I you want to order your boards click on "Buy 3 boards for..." Fill in your order details and you will receive high quality PCBs in about two weeks. With free shipping world wide!
Step 19: Order Your PCB
Now you can order your PCB by clicking the Buy button.