Zone priority for overlapping fills in PCB Design - Real Business Scenario

Scenario Mode

👤 Your Role: You are a PCB designer working on a complex multilayer board.

📋 Request: Your manager wants you to ensure that overlapping copper fills on the same layer respect the correct zone priority to avoid electrical shorts and maintain signal integrity.

📊 Data: You have a PCB design file with multiple copper zones defined on the same layer. Some zones overlap partially or fully. Each zone has a priority level assigned.

🎯 Deliverable: You need to configure the zone priority settings in your PCB design software so that the fills render correctly, with higher priority zones taking precedence over lower priority ones in overlapping areas.

Sample Data

Zone Name	Net	Priority	Area (mm²)	Overlap With
GND_Plane	GND	1	500	Power_Plane
Power_Plane	VCC	2	300	GND_Plane
Signal_Shield	Shield	3	100	Power_Plane
Test_Point	Test	4	10	Signal_Shield

1

Step 1: Open your PCB design software and load the board file containing the overlapping zones.

No formula needed; just open the design file.

Expected Result

The board with all copper zones visible on the same layer.

2

Step 2: Access the zone priority settings or properties panel for copper fills.

Navigate to Design > Zones > Zone Priority or equivalent menu.

Expected Result

Zone priority configuration window opens showing all zones and their current priorities.

3

Step 3: Set the priority values for each zone according to the business rule: higher priority zones override lower ones in overlaps.

Assign priorities as: Test_Point=4, Signal_Shield=3, Power_Plane=2, GND_Plane=1.

Expected Result

Zone priorities updated so that Test_Point has highest priority and GND_Plane the lowest.

4

Step 4: Apply the zone priority settings and regenerate the copper fills on the layer.

Click Apply or OK and then use the Refill Zones command.

Expected Result

Copper fills redraw with overlapping areas showing the higher priority zone's copper.

5

Step 5: Verify visually and with design rule checks that no unintended copper shorts or gaps exist due to overlapping fills.

Run Design Rule Check (DRC) focusing on copper clearance and connectivity.

Expected Result

DRC passes with no errors related to overlapping zones; visual inspection confirms correct fill priority.

Final Result

Test_Point

↓

Signal_Shield

↓

Power_Plane

↓

GND_Plane

✓Higher priority zones correctly override lower priority zones in overlapping areas.

✓No electrical shorts or clearance violations detected after applying zone priorities.

✓Signal integrity is maintained by proper copper fill layering.

Bonus Challenge

Configure zone priorities dynamically using scripting or automation to handle large boards with many overlapping zones.

Show Hint

Use your PCB software's scripting API or batch commands to assign priorities based on net types or area size automatically.