Trace width for current capacity in PCB Design - Real Business Scenario

Scenario Mode

👤 Your Role: You are a PCB design engineer working on a new electronic device.

📋 Request: Your manager wants you to determine the correct trace widths on the PCB to safely carry specified current loads without overheating.

📊 Data: You have a table listing different current values (in Amperes) and the corresponding recommended trace widths (in mils) for a 1 oz copper thickness PCB.

🎯 Deliverable: Create a report with a clear table and a line chart showing the relationship between current and trace width. Include a calculated measure for the minimum trace width needed for a given current.

Sample Data

Current (A)	Trace Width (mils)
1	10
2	20
3	30
4	40
5	50
6	65
7	80
8	95
9	110
10	125

1

Step 1: Load the sample data into your BI tool as a table with columns 'Current (A)' and 'Trace Width (mils)'.

Import the data as-is from the sample_data HTML table.

Expected Result

A table with 10 rows showing current values from 1A to 10A and their corresponding trace widths.

2

Step 2: Create a line chart to visualize the relationship between Current and Trace Width.

Set X-axis to 'Current (A)', Y-axis to 'Trace Width (mils)'.

Expected Result

A smooth increasing line showing trace width growing as current increases.

3

Step 3: Create a calculated measure to find the minimum trace width needed for any given current input.

Use interpolation or lookup to find trace width for input current. For example, in DAX: TraceWidthForCurrent = LOOKUPVALUE('Table'[Trace Width (mils)], 'Table'[Current (A)], SELECTEDVALUE('Input'[Current]))

Expected Result

When input current is 5A, the measure returns 50 mils; for 7A, returns 80 mils.

4

Step 4: Add a slicer or input box for the user to select or enter a current value to see the required trace width.

Connect the slicer/input to the calculated measure from step 3.

Expected Result

User can select current 3A and see trace width update to 30 mils dynamically.

5

Step 5: Format the report with clear labels, titles, and units for accessibility and clarity.

Add chart title 'Trace Width vs Current', axis titles 'Current (A)' and 'Trace Width (mils)'. Ensure color contrast is high.

Expected Result

A clean, readable report suitable for presentation to engineering team.

Final Result

Trace Width vs Current (A)

Current (A) | Trace Width (mils)
------------|--------------------
1           | 10
2           | 20
3           | 30
4           | 40
5           | 50
6           | 65
7           | 80
8           | 95
9           | 110
10          | 125

[Line chart showing an upward slope from 10 mils at 1A to 125 mils at 10A]

User input: 5A -> Required Trace Width: 50 mils

✓Trace width increases roughly linearly with current to prevent overheating.

✓For currents above 5A, trace width grows faster to handle heat dissipation.

✓Using this data helps ensure PCB traces are designed safely for electrical loads.

Bonus Challenge

Extend the report to include trace width recommendations for different copper thicknesses (e.g., 2 oz copper).

Show Hint

Add a new column for copper thickness and adjust trace width values accordingly using industry formulas or tables.