Electronics
Design

Introduction

Electronics design is a fundamental skill in embedded systems and digital fabrication, enabling ideas to be transformed into functional hardware. During this week, we studied essential electronic components — resistors, capacitors, diodes, transistors, voltage regulators, microcontrollers, sensors, and actuators — and the electrical principles governing them, including voltage, current, power, and Kirchhoff's laws.

We explored Electronic Design Automation (EDA) tools for schematic capture, PCB layout, simulation, and fabrication. Practical experience was gained using laboratory test equipment: multimeters, regulated power supplies, oscilloscopes, and logic analyzers to observe the behavior of embedded microcontroller systems.

Assignments

Tools & Software Used

KiCad was the primary EDA platform — a single, unified open-source software that bundles all the tools needed to go from schematic to fabrication-ready files. Its compatibility with the Fab Academy library made it the ideal choice for this week's work.

Board Functional Blocks

The custom ESP32-S board was organized into four functional blocks — each serving a critical role in making the board reliable, programmable, and extensible.

Step-by-Step Process

The full board design followed a structured workflow — from software setup and library configuration through schematic, layout, verification, and final export.

Step 01

Software Installation: KiCad

Downloaded KiCad from the official website and installed the full suite: Schematic Editor, PCB Editor, Symbol and Footprint Libraries, and the 3D Viewer. Launched KiCad and verified all modules run correctly before beginning.

KiCad 7+Schematic EditorPCB Editor3D Viewer

KiCad launched and ready

Step 02

Adding the Fab KiCad Library

Downloaded the Fab KiCad library from the Fab Academy repository. During installation, I opened the Plugins and Content Manager, searched for FABLIB, clicked Install, and applied pending changes.

Fab LibrarySymbol LibraryFootprint Library

Searching FABLIB in Plugins and Content Manager

Fab Academy library successfully installed

Step 03

Schematic Design

Placed all components: ESP32-S, voltage regulators, resistors, BOOT and EN buttons, and GPIO headers. Connected power rails and signal pins, and added net labels for clarity. Ran ERC and resolved all errors before proceeding to layout.

ESP32-SNet LabelsERC Passed

ESP32-S placed in schematic

Power regulation — 3.3V input section

Adding other components

Adding communication interfaces

Step 04

Footprint Assignment

Assigned physical footprints to every symbol in the schematic using the Footprint Assignment tool. Cross-referenced each footprint with the lab's physical component inventory to confirm availability. Verified all links were clean before pushing to PCB layout.

SMD FootprintsThrough-HoleFab Inventory

Footprint assignment tool

Step 05

PCB Editor & Manual Routing

Switched to the PCB Editor and imported the schematic. Defined the board outline and overall dimensions. Placed the ESP32-S centrally and arranged support components near their related pins. Set global track width to 0.8 mm. Manually routed all signal and power traces, maintaining proper clearances and eliminating all shorts.

0.8mm TracksManual RoutingBoard Outline

Design Rule: All traces were kept at 0.8 mm minimum width to ensure reliable fabrication on the lab's milling machine. Power traces were kept short and direct to minimize resistance and voltage drop.

Step 06

Design Rule Check (DRC)

Ran the full DRC suite in KiCad's PCB Editor. Resolved all flagged violations — primarily clearance violations near the header pins and a missing courtyard on one component. After corrections, the board passed all checks with zero errors.

DRCZero ErrorsClearance Check

DRC completed — 0 errors, 0 warnings

Step 07

3D View of the PCB

Used KiCad's integrated 3D Viewer to inspect the completed board. Verified correct placement and orientation of all components — particularly the ESP32-S module, voltage regulator, and button positions — before generating fabrication files.

3D RenderVisual Inspection

KiCad 3D Viewer — full board visualization

Step 08

Circuit Simulation

Simulated a basic LED with current-limiting resistor to validate resistor value selection, then simulated the voltage regulator circuit to confirm output stability at 3.3V under varying load conditions. Both simulations ran correctly in KiCad's SPICE engine.

SPICE SimulationLED CircuitVoltage Regulator

SPICE simulation — voltage regulator output at 3.3V

Step 09

Exporting Fabrication Files

Generated full Gerber files (copper layers, silkscreen, solder mask, board outline) and an Excellon drill file. Verified the export using an online Gerber viewer before archiving. Files are ready for milling or PCB fabrication.

Gerber FilesDrill FileFabrication Ready

Files exported: ├── board-F_Cu.gbr (Front copper layer) ├── board-B_Cu.gbr (Back copper layer) ├── board-F_SilkS.gbr (Silkscreen) ├── board-Edge_Cuts.gbr (Board outline) └── board-PTH.drl (Drill file)

Conclusion