Most PCBs are designed to be as small as possible, but that’s not necessary if your application doesn’t require it. It’s not uncommon to see round, triangular, or other interesting PCB shapes. If sections are connected in a daisy-chain configuration, the current drawn from sections closer to the supply will create a voltage drop and result in lower voltages at sections further from the supply: This is called a star configuration, and it ensures that each section gets an equal supply voltage. The signals in your circuit should flow in a direct path from one section to another, which will keep the traces shorter.Įach section of the circuit should be supplied power with separate traces of equal length. The different sections of your circuit should be arranged so the path of electrical current is as linear as possible. Long traces can pick up electromagnetic radiation from other sources, which can cause interference and noise. Keep the components in each section grouped together in the same area of the PCB to keep the conductive traces short. For example, my LM386 audio amplifier circuit has four main sections: a power supply, an audio input, the LM386, and an audio output. It might help to draw some diagrams at this point to help you visualize the design before you start laying it out. Identify what each part of your circuit does, and divide the circuit into sections according to function. The next step is to import the schematic into the PCB editor, but before we do that, let’s talk about some things to keep in mind when designing your PCB. The labels will be transferred over to the PCB layout and eventually be printed on the finished PCB. Each symbol has a name (R1, R2, C1, C2 etc.) and value (10 μF, 100 Ω, etc.) that can be edited by clicking on the label. Rather than explain the details of all that in this article, I’ve made a video so you can watch me draw the schematic for my LM386 audio amplifier:Īfter all the wiring is done, it’s a good idea to label the symbols. Once all of your symbols are placed on the schematic and you’ve assigned footprints to each symbol, it’s time to start drawing the wires. Now click on the symbol in the schematic editor, and paste the name of the new footprint into the “package” field in the right sidebar menu (watch the video below for a demonstration): Once you find it, click on the heart icon to “Favorite” it: To change the footprint associated with a schematic symbol, search in the “User Generated” libraries for a footprint that matches the component you’re using. The schematic symbols in the EasyEDA library already have footprints associated with them, but they can be changed if your’re using a different size or style: Now is a good time to decide which components you’ll be using. The PCB footprint will define the component’s physical dimensions and placement of the copper pads or through holes. The default EasyEDA library has most of the common symbols, but there are also “User Generated Libraries” with lots of other symbols:Įach schematic symbol you use needs to have a PCB footprint associated with it. In EasyEDA, schematic symbols are located in “Libraries”. It’s best to place all of your schematic symbols on the canvas before drawing any wires. Now you’ll see a blank canvas where you can draw the schematic: Once you’re on the Start page, click on the “new Schematic” tab: Start by logging in to EasyEDA, and create a new project: Plus, the PCB editing software can import all of the components, footprints, and wires into the PCB file, which will make the design process easier (more on this later). The schematic will serve as a blueprint for laying out the traces and placing the components on the PCB. It All Starts With a Schematicīefore you start designing your PCB, it’s a good idea to make a schematic of your circuit. To demonstrate the process, I’ll use an online service called EasyEDA to design a PCB layout for an LM386 audio amplifier, then I’ll have it manufactured and show you the results. Their free online design software is easy to use and the rates are very affordable. But that method is messy and it uses a lot of chemicals. It’s much easier (and cheaper) to get your PCB made by a professional manufacturer. You can always etch PCBs at home with a process that’s similar to developing prints from photographic film. The performance of your circuit will depend greatly on how it’s laid out on the PCB, so I’ll give you lots of tips on how to optimize your design. In this tutorial, I’ll walk you through the process of designing a PCB layout and getting it printed by a custom PCB manufacturer.
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