KiCad 9.0 - Getting Started Part 5 - Assigning & Creating Custom Footprints_DigiKey

Episode 5: Assigning Footprints and Creating a Custom Buzzer Footprint in KiCad In this episode of the KiCad water alarm project, we shift from the schematic to preparing for layout by assigning physical footprints to each of our components. You'll learn how to match schematic symbols with their corresponding PCB footprints using KiCad’s built-in libraries, and we’ll go a step further by creating a fully custom footprint for the buzzer, complete with a 3D model. We start in the Schematic Editor by opening the spreadsheet-style symbol manager. Here, you’ll clean up the view by hiding unnecessary columns and adding a custom DK_PN field for Digi-Key part numbers. This helps organize and prepare the Bill of Materials (BOM) for later stages. Each part is listed with its value and part number, and we walk through exactly where to enter those values. Next, we assign standard footprints for most of the components. The buzzer, however, is where the real fun begins. We walk step-by-step through creating a custom footprint in KiCad’s Footprint Editor. Starting from the manufacturer datasheet, we extract key dimensions like pin spacing (15mm), hole diameter (1mm), and body size (30.2mm diameter, 20mm height). Using this data, we: • Create a new footprint library for custom parts. • Add through-hole pads with proper shapes and dimensions. • Add reference designators and silk screen features for clarity and polarity. • Build outline shapes on the fabrication and courtyard layers. • Add polarity indicators on both the top and bottom silk screen layers. • Insert a 3D model by downloading a STEP file from the manufacturer’s page and aligning it visually using rotation and offset tools.

You’ll also learn practical tips like:

• Why KiCad uses square pads for Pin 1 on polarized components. • How to draw precisely sized circles using radius snapping or manual entry. • How to avoid common layer assignment mistakes when placing pads. • How to rotate and flip 3D models to align them accurately with your layout. Once the custom buzzer footprint is complete, we return to the schematic editor and assign the new footprint to our buzzer symbol. The table now shows a fully populated list of components, values, Digi-Key part numbers, and corresponding footprints—ready for PCB layout. This episode bridges the schematic and PCB design phases, teaching you how to organize, assign, and even build footprints with confidence. By the end, you’ll understand how footprint names reflect physical dimensions, how to read datasheets for layout purposes, and how to bring real-world components into your digital design environment.

Coming up in Episode 6: We move into the PCB Editor to place and route our newly assigned footprints, visualize the 3D layout, and prepare the board for manufacturing.