1. Open the PCB Layout Editor:
   • Navigate to the PCB layout editor where you can view and modify the layers of your PCB design.
2. Select the Desired Layer:
   • Choose the layer you want to work on by selecting it from the layer stack or layer navigator.
3. Edit or Add a Polygon Pour:
   • If you want to edit an existing pour, select the polygon pour on the canvas.
   • If you want to add a new pour, use the polygon tool to draw the desired shape for the pour on the selected layer.
4. Modify Pour Properties:
   • Adjust properties such as net association, clearance, fill style, and more. These settings can typically be found in the properties panel or a context menu when the pour is selected.
5. Apply Changes:
   • Once you have configured the pour settings to your liking, apply the changes. The tool should automatically update the pour based on the new settings.

1. Power and Ground Nets:
   • The 3V3 net correctly connects the power pins of your ESP32, OLED, and VOLUME Encoder. Ensure the trace width is sufficient for the current capacity.
   • The GND net looks fine as well, connecting the grounds of the ESP32, OLED, and the switches.
2. OLED Display Connections:
   • Connections are:
     • Connect $OLED:GND$ to $ESP32:GND$.
     • Connect $OLED:VDD$ to $ESP32:3V3$.
     • Connect $OLED:SCL$ to $ESP32:D22$.
     • Connect $OLED:SDA$ to $ESP32:D21$.
   • SDA and SCL lines should have pull-up resistors, typically 4.7kΩ or 10kΩ to 3.3V.
3. Switch Connections:
   • Next:
     • Connect $NEXT:P1$ to $ESP32:D19$.
     • Connect $NEXT:P2$ to $GND$.
   • Play:
     • Connect $PLAY:P1$ to $ESP32:D18$.
     • Connect $PLAY:P2$ to $GND$.
   • Prev:
     • Connect $PREV:P1$ to $ESP32:D5$.
     • Connect $PREV:P2$ to $GND$.
   • Ensure debouncing either in hardware (using capacitors) or in software.
4. Volume Encoder Connections:
   • Connections are:
     • Connect $VOLUME:CLK$ to $ESP32:D4$.
     • Connect $VOLUME:DT$ to $ESP32:D2$.
     • Connect $VOLUME:SW$ to $ESP32:D15$.
     • Connect $VOLUME:VCC(+)$ to $3V3$.
     • Connect $VOLUME:GND$ to $GND$.

1. Pull-Up Resistors:
   • Ensure pull-up resistors are in place for I2C lines (SCL and SDA).
2. Trace Width:
   • Verify that the width of power and ground traces can handle the current requirements.
3. Signal Integrity:
   • Ensure signal traces, especially for I2C, are not too long and are as direct as possible to avoid noise and signal integrity issues.
4. Debouncing:
   • Ensure a method for switch debouncing is implemented, either through hardware (capacitors) or software.
5. General Layout:
   • Check for a good layout practice, such as minimizing the loop areas for signal integrity and ensuring components are placed logically and close to related components.

• Current: 600mA
• Copper Thickness: 1 oz/ft² (common in PCB manufacturing)
• Temperature Rise: 10°C (standard for most designs)

• $W$ is the width of the track.
• $I$ is the current in Amperes (A).
• $R_{\text{temp}}$ is the allowed temperature rise (in °C).
• $K$ is a constant (0.024 for internal layers, 0.048 for external layers).
• $C_{\text{thickness}, \text{micro}}$ is the copper thickness in micrometers (1 oz/ft² ≈ 35μm).

Python
import math

# Constants for IPC-2221 standard formula
current = 0.6  # Current in Amperes
temperature_rise = 10  # Temperature rise in °C

# Constant for external layers
K_external = 0.048

# Calculate the trace width in mils
trace_width_mils = (K_external * (current ** 0.725)) / (temperature_rise ** 0.44)

# Convert mils to mm (1 mil = 0.0254 mm)
trace_width_mm = trace_width_mils * 0.0254
trace_width_mm

• Trace Width: Ensure your 3.3V power trace width is at least 0.31 mm.
• Preferred Width: To be cautious and factor in manufacturing tolerances, you might want to round up to the nearest typical multiple (e.g., 0.5 mm).

1. Keep Traces Short: For I2C (SDA and SCL), keeping traces under 10 cm is ideal to minimize noise and ensure signal integrity.
2. Avoid Crosstalk: Route SDA and SCL away from high-speed or noisy traces.
3. Ground Plane: Ensure a solid ground plane beneath the I2C traces to shield them from interference.
4. Pull-up Resistors: Use 4.7kΩ pull-up resistors on SDA and SCL lines.

• OLED SDA to ESP32 D21: Ensure this trace is short and direct.
• OLED SCL to ESP32 D22: Ensure this trace is short and direct.

• Place the OLED Display: As close to the ESP32 as possible to keep signal traces short.
• Route Directly: Route the I2C lines directly without unnecessary vias or loops.
• Shielding: If possible, add ground pours around the I2C lines for additional protection.