Via size and drill diameter in PCB Design - Real Business Scenario

Scenario Mode

👤 Your Role: You are a PCB design analyst at an electronics manufacturing company.

📋 Request: Your manager wants a report showing the relationship between via sizes and drill diameters used in recent PCB designs to optimize manufacturing costs and reliability.

📊 Data: You have a dataset listing various PCB designs with columns for Via Size (in mils), Drill Diameter (in mils), and Quantity used in each design.

🎯 Deliverable: Create a dashboard that summarizes average drill diameter by via size category and total quantity used, with a visualization that helps identify optimal via and drill size combinations.

Sample Data

PCB Design	Via Size (mils)	Drill Diameter (mils)	Quantity
Design A	12	10	150
Design B	15	13	200
Design C	12	11	180
Design D	20	18	120
Design E	15	14	160
Design F	20	19	140
Design G	12	10	170
Design H	15	13	190

1

Step 1: Load the PCB design data into your BI tool.

Import the table with columns: PCB Design, Via Size (mils), Drill Diameter (mils), Quantity.

Expected Result

Data table with 8 rows loaded correctly.

2

Step 2: Create a calculated measure to find the average Drill Diameter for each Via Size.

Average Drill Diameter = AVERAGE('Table'[Drill Diameter (mils)]) grouped by 'Table'[Via Size (mils)]

Expected Result

Average drill diameters calculated per via size: 12 mils -> 10.33, 15 mils -> 13.33, 20 mils -> 18.5

3

Step 3: Create a calculated measure to find the total Quantity used for each Via Size.

Total Quantity = SUM('Table'[Quantity]) grouped by 'Table'[Via Size (mils)]

Expected Result

Total quantities per via size: 12 mils -> 500, 15 mils -> 740, 20 mils -> 260

4

Step 4: Build a bar chart visualization with Via Size on the X-axis and two bars per via size: one for Average Drill Diameter and one for Total Quantity (use secondary axis for quantity).

Configure chart: X-axis = Via Size (mils), Y-axis left = Average Drill Diameter, Y-axis right = Total Quantity

Expected Result

Bar chart shows average drill diameter and total quantity side by side for each via size.

5

Step 5: Add data labels to the bars for clarity and ensure color contrast for accessibility.

Enable data labels on both bars; use distinct colors with good contrast.

Expected Result

Chart clearly shows numeric values on bars, easy to read and interpret.

Final Result

Via Size (mils) | Avg Drill Diameter | Total Quantity
-----------------------------------------------------
12               | ########## 10.33   | ########### 500
15               | ############ 13.33 | ############### 740
20               | ############## 18.5| ####### 260

Bar chart with two bars per via size: left bar (avg drill diameter), right bar (total quantity).

✓Via size 15 mils has the highest total quantity used, indicating it is the most common.

✓Average drill diameter increases with via size as expected.

✓Via size 20 mils has the largest drill diameter but lower quantity, suggesting it is less common but used for specific needs.

Bonus Challenge

Create a drill-down feature in the dashboard to see individual PCB designs contributing to each via size category.

Show Hint

Use drill-through or filter actions in your BI tool to link from via size summary to detailed design rows.