PCB Guide 4 - The rest of the schematic

IN PROGRESS
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By this point, you should have the MCU schematic zone complete.

Step 6. The rest of the schematic

The rest of the schematic is not as difficult as the MCU.
Let's power through it.

USB circuitry

Only typical Mini-B USB will be covered here for simplicity reasons?
Type-C setups will be discussed in future sections.

Search for the molex USB connector in my library, along with polyfuse-small.

Connect VBUS -> Polyfuse, then Polyfuse -> +5V. Drop a VCC symbol pre-fuse. Change fuse value to 500mA.

The rest are self-explanatory. The data lines are connected using the global labels we set up earlier:

Switch matrix

Now, let's add the switch matrix.
I will use the MX-1U symbol from my own library.

Combine it with a D_Small (small diode). Ignore the LED pads for now; that will be covered later.
Connect the anode of the diode to the ROW pin of the switch.

Now clone this four times as shown:

Then, drag a wire across the diode cathode and COL pins of each row and column, and terminate them using the hotkey k:

Finally, add global labels for each row and column. It is recommended to label them counting from 0 up, since that is how it is handled firmware side as well.

Note that we will NOT be connecting the rows and columns to the MCU just yet.

Finally, a schematic is complete. 

However, there's one one more step before getting to work on the physical PCB.