Key Engineering Takeaways
- •Custom 2-layer PCBs cost as little as $2 for 5 boards and eliminate 99% of hand-wiring mistakes.
- •KiCad is the premier open-source industrial standard EDA suite; EasyEDA is a fast, web-based tool with direct LCSC component library integration.
- •Every schematic symbol must be linked to a physical land pattern footprint (e.g. DIP-8, 0805 SMD, TO-220).
- •Use thick traces (20-40 mils) for power/ground rails and thin traces (8-12 mils) for low-frequency digital signals.
- •Always fill the top and bottom layers with continuous Ground Copper Pours (GND plane) to minimize electromagnetic interference (EMI).
Prerequisites
- • Schematic reading and circuit design fundamentals
Required Hardware / Tools
- • PC with KiCad 8.x or Modern Web Browser for EasyEDA
- • Fabricated Custom PCB
- • Soldering Station and Components
Why Design Custom PCBs? Quality, Size & Cost
A **Printed Circuit Board (PCB)** replaces hand-soldered wires with precise copper traces etched onto an epoxy fiberglass substrate.
### Advantages of Custom PCBs:
- **Miniaturization**: Reduces circuit footprint by up to 80% using Surface Mount Devices (SMD).
- **Zero Wiring Errors**: Traces are manufactured exactly according to your verified schematic.
- **Affordable Fabrication**: Rapid fab houses (JLCPCB, PCBWay, OSH Park) fabricate 5 custom 2-layer PCBs for just **2 to5** with a 3-day turnaround!
Choosing Your EDA Tool: KiCad 8 vs EasyEDA
### 1. KiCad (Recommended Open-Source Standard):
- Free, completely open-source, with no board size or layer limitations.
- Extensive 3D model visualization and powerful push-and-shove trace routing.
- Industry-standard software used by professional hardware startups and research labs.
### 2. EasyEDA:
- Runs directly inside your web browser.
- Direct integration with LCSC parts catalog and JLCPCB ordering with 1-click SMT assembly.
Step 1: Schematic Capture & Footprint Assignment
1. **Schematic Editor**: Place your symbols (ESP32, motor driver, 5V regulator, decoupling caps) and wire all nets.
2. **Electrical Rules Check (ERC)**: Run ERC to detect uncommitted pins, missing power flags, or unconnected inputs.
3. **Footprint Assignment**: Map each schematic symbol to its physical hardware package:
- Resistors: Through-hole 0.25W (7.62 mm span) or `0805` SMD.
- Connectors: `JST-XH-2.54mm` or `TerminalBlock-5.08mm`.
4. Click **Update PCB from Schematic** (F8 in KiCad).
ERC RuleNever begin routing traces on your PCB until your schematic passes Electrical Rules Check with zero errors!
Step 2: PCB Layout, Trace Widths & Solid Ground Pours
### Golden Routing Rules for Robotics:
1. **Component Placement First**: Position connectors along the board edge and decoupling capacitors within 2 mm of IC supply pins.
2. **Trace Width Sizing**:
- Signal Traces (3.3V logic): **0.25 mm (10 mils)**
- Power Traces (5V / 1A): **0.8 mm - 1.0 mm (32-40 mils)**
- Motor Power (12V / 5A): **2.5 mm+ (100 mils)** or unmasked copper pour with solder reinforcement.
3. **Ground Copper Zone (GND Fill)**: Pour a solid copper zone on both top and bottom layers assigned to the `GND` net. This provides a low-impedance return path for currents, shielding signals from motor noise.
Step 3: DRC Checks & Generating Gerber Production ZIPs
1. **Design Rules Check (DRC)**: Verifies minimum trace spacing (6 mils), minimum hole drill diameters (0.3 mm), and clearance to board edges according to fab house specifications.
2. **Plot Gerber Files**:
- Copper Layers (Top / Bottom)
- Solder Mask (Top / Bottom)
- Silkscreen (Top / Bottom)
- Edge.Cuts (Board outline)
- Drill File (`.xln` / `.drl`)
3. Compress all generated files into a single **`production_gerbers.zip`**.
4. Upload the ZIP directly to JLCPCB/PCBWay, inspect the automatic online 3D Gerber viewer, and place your order!
Frequently Asked Questions
What is the standard PCB thickness and copper weight?
The universal standard is 1.6mm board thickness with 1 oz/ft² (35µm) copper layer thickness. For high-current combat robots (>15A), select 2 oz (70µm) copper.
What is a Solder Mask and Silkscreen?
The Solder Mask is the protective lacquer layer (commonly green, matte black, or blue) that prevents solder bridges between adjacent copper traces. The Silkscreen is the printed white text layer indicating component labels (R1, C1, VCC, GND, Logo).
Tags:#PCB Design#KiCad#EasyEDA#JLCPCB#Gerbers#Hardware Engineering