PCB material and copper weight basics in PCB Design - Dashboard Guide

Dashboard Mode - PCB material and copper weight basics

Goal

Understand how different PCB materials and copper weights affect cost and performance.

Sample Data

Material	Copper Weight (oz)	Cost per sq.ft ($)	Thermal Conductivity (W/mK)	Typical Use
FR4	1	2.50	0.3	General purpose
FR4	2	3.50	0.3	Higher current
Polyimide	1	4.00	0.4	High temp
Polyimide	2	5.00	0.4	High temp, high current
Rogers	1	6.00	0.9	High frequency
Rogers	2	7.50	0.9	High freq, high current
Aluminum	1	8.00	2.0	LED boards
Aluminum	2	9.50	2.0	High power LED

Dashboard Components

• KPI Card: Average Cost per Material
  Formula: Average Cost = AVERAGE('Cost per sq.ft ($)')
  Shows the average cost for each material type.
• Bar Chart: Cost by Material and Copper Weight
  X-axis: Material
  Y-axis: Cost per sq.ft ($)
  Legend: Copper Weight (1 oz, 2 oz)
  Shows how cost changes with copper weight for each material.
• Table: Detailed Data
  Shows all columns from the sample data for reference.
• Scatter Plot: Thermal Conductivity vs Cost
  X-axis: Thermal Conductivity (W/mK)
  Y-axis: Cost per sq.ft ($)
  Points colored by Material
  Shows relationship between thermal conductivity and cost.

Dashboard Layout

+----------------------+--------------------------+
|  KPI: Avg Cost       |  Bar Chart: Cost by       |
|  per Material        |  Material & Copper Weight |
|                      |                          |
+----------------------+--------------------------+
|                      |                          |
|  Table: Detailed Data |  Scatter Plot: Thermal   |
|                      |  Conductivity vs Cost    |
+----------------------+--------------------------+
  

Interactivity

Filter by Material: Selecting a material filters the bar chart, scatter plot, and table to show only that material's data. The KPI card updates to show the average cost for the selected material.

Filter by Copper Weight: Selecting 1 oz or 2 oz filters the bar chart, scatter plot, and table accordingly. KPI updates average cost for the filtered data.

Self Check

If you add a filter for Material = 'FR4', which components update?

• KPI Card updates to show average cost for FR4 only.
• Bar Chart shows cost bars only for FR4 copper weights.
• Scatter Plot shows points only for FR4.
• Table shows only rows where Material is FR4.

Key Result

Dashboard showing cost, thermal conductivity, and typical uses for PCB materials and copper weights.

Practice

1. Which property of PCB material mainly affects the board's ability to withstand heat?

easy

A. Copper weight

B. Thermal resistance

C. Board thickness

D. Solder mask color

Solution

1. Step 1: Understand PCB material properties

   PCB materials are chosen for their ability to resist heat and mechanical stress.

2. Step 2: Identify the key property for heat resistance

   Thermal resistance measures how well the material withstands heat without damage.

3. Final Answer:

   Thermal resistance -> Option B

4. Quick Check:

   Heat resistance = Thermal resistance [OK]

Hint: Heat resistance relates to material's thermal resistance [OK]

Common Mistakes:

• Confusing copper weight with heat resistance
• Thinking board thickness controls heat tolerance
• Assuming solder mask color affects heat resistance

2. Which of the following correctly describes copper weight in PCB design?

easy

A. Thickness of copper layer measured in ounces per square foot

B. Color of the copper layer

C. Length of copper traces on the board

D. Weight of the entire PCB

Solution

1. Step 1: Define copper weight

   Copper weight refers to the thickness of the copper layer on the PCB, usually measured in ounces per square foot.

2. Step 2: Eliminate incorrect options

   Color, length of traces, and total PCB weight do not define copper weight.

3. Final Answer:

   Thickness of copper layer measured in ounces per square foot -> Option A

4. Quick Check:

   Copper weight = Thickness in oz/ft² [OK]

Hint: Copper weight means thickness in ounces per square foot [OK]

Common Mistakes:

• Confusing copper weight with PCB color
• Thinking copper weight is trace length
• Assuming copper weight is total board weight

3. If a PCB uses 2 oz copper weight instead of 1 oz, what is the main effect on current carrying capacity?

medium

A. It reduces the current carrying capacity by 25%

B. It halves the current carrying capacity

C. It has no effect on current carrying capacity

D. It doubles the current carrying capacity

Solution

1. Step 1: Understand copper weight impact

   Copper weight thickness directly affects how much current the PCB trace can safely carry.

2. Step 2: Compare 1 oz and 2 oz copper

   Doubling copper weight from 1 oz to 2 oz roughly doubles the cross-sectional area, thus doubling current capacity.

3. Final Answer:

   It doubles the current carrying capacity -> Option D

4. Quick Check:

   2 oz copper = double current capacity [OK]

Hint: Double copper weight roughly doubles current capacity [OK]

Common Mistakes:

• Assuming copper weight does not affect current
• Thinking current capacity halves with more copper
• Confusing copper weight with board thickness

4. A PCB designer wrote: "Using 0.5 oz copper weight will increase current capacity compared to 1 oz copper." What is wrong with this statement?

medium

A. 0.5 oz copper weight decreases current capacity compared to 1 oz

B. Copper weight does not affect current capacity

C. 0.5 oz copper weight is thicker than 1 oz

D. Current capacity depends only on board size

Solution

1. Step 1: Analyze copper weight values

   0.5 oz copper is thinner than 1 oz copper, so it carries less current.

2. Step 2: Identify the error in the statement

   The statement incorrectly claims 0.5 oz increases current capacity, which is false.

3. Final Answer:

   0.5 oz copper weight decreases current capacity compared to 1 oz -> Option A

4. Quick Check:

   Less copper = less current capacity [OK]

Hint: Less copper weight means less current capacity [OK]

Common Mistakes:

• Thinking thinner copper carries more current
• Ignoring copper weight effect on current
• Confusing copper weight with board size

5. A PCB project requires high durability and the ability to carry 3 times the current of a standard 1 oz copper PCB. Which combination is best?

hard

A. Use low thermal resistance material with 2 oz copper weight

B. Use standard material with 1 oz copper weight and thicker board

C. Use a high thermal resistance material with 3 oz copper weight

D. Use high thermal resistance material with 0.5 oz copper weight

Solution

1. Step 1: Identify durability requirement

   High durability means choosing a PCB material with high thermal resistance to withstand heat and stress.

2. Step 2: Calculate copper weight for current capacity

   To carry 3 times the current of 1 oz copper, use approximately 3 oz copper weight.

3. Step 3: Match material and copper weight

   Combining high thermal resistance material with 3 oz copper meets both durability and current needs.

4. Final Answer:

   Use a high thermal resistance material with 3 oz copper weight -> Option C

5. Quick Check:

   Durability + 3x current = High thermal resistance + 3 oz copper [OK]

Hint: Match high thermal resistance with needed copper weight [OK]

Common Mistakes:

• Ignoring material thermal resistance for durability
• Using too low copper weight for current needs
• Assuming thicker board replaces copper weight