The schematic. It’s where we layout all of our components and their connections, which will make it easy for us to understand our objective while designing the physical layout later on.
Sometimes, you can order your board to be manufactured and assembled with SMD parts from the factory (like at JLCPCB or PCBWay). In that case, you’ll need to lookup your board manufacturer’s database of available components (often LCSC).
If you just want to get your board printed and then solder the components yourself, you’ll probably want to use DigiKey for component orders. Regardless, you’ll be using their search function a lot when creating your schematic, so here’s a rundown of how it works.
DigiKey Canadian homepage.
When searching for components, you can type in (for example) “resistor” and it will often give you categories to select from. When you know exactly what you want, you can type in an exact product number to get a direct result.
Search result after searching for ‘resistor’.
In this case, it’s a good idea to select ‘Chip Resistor - Surface Mount’, because there’s no need to use the less space-efficient through-hole resistors on an integrated PCB.
From here, you can search for your desired resistor. You’ll often want to sort for a specific resistance, as well as pick a reasonable package size, as 0402 and smaller are quite hard to solder yourself (which you’d be doing if you ordered the parts of off DigiKey and the board with a solder stencil from JLCPCB or PCBWay). For those reasons, picking an 0603 part or bigger is a good idea - just make sure they aren’t so big that your board ends up being too large. Bigger components may also come with different power dissipation ratings.
Open Altium Designer and go to File → New → Project… to create a new project. Make sure your project type is PCB and name your project appropriately. Hit ‘Create’ in the bottom right of the window.
Next, you want to add a schematic to your empty project folder. Do so by right clicking on your project in the Projects panel and selecting ‘Schematic’ from the ‘Add New to Project’ dropdown menu.
With the schematic open, we can begin dragging in parts. Feel free to rename your .SchDoc file to something appropriate.
Clicking on the yellow chip symbol (Place Part) will bring up the Components menu, where you can search and select for parts.
Now, in some cases (and in the case that you were building a hobbyist project by yourself), the easiest way to find and import parts into your schematic would be to use Altium’s built-in ‘Manufacturer Part Search’ function (can be opened from ‘Panels’ in the bottom right → ‘Manufacturer Part Search’). This feature is fairly reliable for symbol and footprint quality, and parts come linked to DigiKey, Mouser, etc., with live price updates and other neat features.
However, many other orgs and companies (including Waterloo Reality Labs) use their own custom library to build devices - and for that reason, we’ll have you practice creating custom symbols and footprints. We recommend you make one for the LDO you end up selecting. You can drag in the rest of your components from the Manufacturer Part Search if you’d like.