Cost vs complexity trade-off in PCB Design - Dashboard Approaches Compared

Dashboard Mode - Cost vs complexity trade-off

Dashboard Goal

Understand how the cost of PCB designs changes as their complexity increases to help make better design decisions.

Sample Data

Design ID	Complexity Score	Cost (USD)	Layers	Components Count
D001	3	1200	2	50
D002	5	2500	4	120
D003	7	4000	6	200
D004	4	1800	3	80
D005	6	3200	5	150
D006	8	4500	8	250

Dashboard Components

• KPI Card: Average Cost
  Formula: Average of Cost (USD) = (1200+2500+4000+1800+3200+4500)/6 = 2866.67 USD
• KPI Card: Average Complexity
  Formula: Average of Complexity Score = (3+5+7+4+6+8)/6 = 5.5
• Scatter Plot: Cost vs Complexity
  X-axis: Complexity Score
  Y-axis: Cost (USD)
  Points: Each Design ID plotted by its complexity and cost
• Bar Chart: Layers per Design
  X-axis: Design ID
  Y-axis: Layers
  Shows how many layers each design has
• Table: Detailed Design Data
  Shows all columns from sample data for reference

Dashboard Layout

+----------------------+-----------------------+
| Average Cost (KPI)   | Average Complexity (KPI)|
+----------------------+-----------------------+
|                                              |
|           Scatter Plot: Cost vs Complexity   |
|                                              |
+----------------------+-----------------------+
| Bar Chart: Layers per Design                  |
+----------------------------------------------+
| Table: Detailed Design Data                   |
+----------------------------------------------+
    

Interactivity

Filter by Complexity Score range: When the user selects a complexity range, all components update to show only designs within that range.

Filter by Layers: Selecting specific layer counts filters the scatter plot, bar chart, and table to those designs.

Hovering over points in the scatter plot highlights the corresponding row in the table and bar in the bar chart.

Self Check

If you add a filter to show only designs with Complexity Score greater than or equal to 6, which components update and what changes occur?

• Average Cost KPI updates to average cost of designs D003, D005, D006 = (4000+3200+4500)/3 = 3900 USD
• Average Complexity KPI updates to average complexity of these designs = (7+6+8)/3 = 7
• Scatter plot shows only points for D003, D005, D006
• Bar chart shows layers for D003, D005, D006 only
• Table filters to show only rows for D003, D005, D006

Key Result

Dashboard showing how PCB design cost increases with complexity, layers, and components count.

Practice

1.

What does the term cost vs complexity trade-off mean in PCB design?

easy

A. Balancing the expense of manufacturing with how complicated the design is

B. Choosing the most complex design regardless of cost

C. Always selecting the cheapest materials without considering design

D. Ignoring design complexity to speed up production

Solution

1. Step 1: Understand the terms cost and complexity

   Cost refers to money spent, complexity refers to how difficult the PCB design is.

2. Step 2: Define trade-off in this context

   Trade-off means finding a balance between cost and complexity to optimize both.

3. Final Answer:

   Balancing the expense of manufacturing with how complicated the design is -> Option A

4. Quick Check:

   Cost vs complexity = balance [OK]

Hint: Think balance between money and design difficulty [OK]

Common Mistakes:

• Assuming cheapest always best
• Ignoring design complexity
• Confusing cost with time

2.

Which of the following is the correct way to express a simple cost calculation in PCB design?

Cost = Number_of_layers * Cost_per_layer

easy

A. Cost = Number_of_layers * Cost_per_layer

B. Cost = Number_of_layers + Cost_per_layer

C. Cost = Number_of_layers / Cost_per_layer

D. Cost = Cost_per_layer - Number_of_layers

Solution

1. Step 1: Identify the correct arithmetic operation for total cost

   Total cost is calculated by multiplying the number of layers by the cost per layer.

2. Step 2: Check each option for correctness

   Only Cost = Number_of_layers * Cost_per_layer uses multiplication which correctly models total cost.

3. Final Answer:

   Cost = Number_of_layers * Cost_per_layer -> Option A

4. Quick Check:

   Cost = layers x cost per layer [OK]

Hint: Multiply layers by cost per layer for total cost [OK]

Common Mistakes:

• Using addition instead of multiplication
• Dividing cost per layer by layers
• Subtracting layers from cost

3.

Given the following data for two PCB designs:

• Design A: 4 layers, $10 per layer, complexity score 3
• Design B: 6 layers, $8 per layer, complexity score 5

Which design has the lower total cost?

medium

A. Design A with total cost $24

B. Design A with total cost $40

C. Design B with total cost $48

D. Design B with total cost $30

Solution

1. Step 1: Calculate total cost for Design A

   4 layers x $10 = $40 total cost.

2. Step 2: Calculate total cost for Design B

   6 layers x $8 = $48 total cost.

3. Final Answer:

   Design A with total cost $40 -> Option B

4. Quick Check:

   4x10=40 < 6x8=48 [OK]

Hint: Multiply layers by cost per layer, compare totals [OK]

Common Mistakes:

• Mixing up costs between designs
• Ignoring multiplication
• Confusing complexity score with cost

4.

Identify the error in this cost calculation formula for PCB design:

Cost = Number_of_layers + Cost_per_layer * Complexity_score

medium

A. Complexity_score should not be included in cost calculation

B. Multiplication should be done before addition using parentheses

C. The formula should use addition only, no multiplication

D. The formula should multiply Number_of_layers by Cost_per_layer first

Solution

1. Step 1: Analyze the intended cost components

   Cost depends on number of layers and cost per layer multiplied, complexity affects design but not direct cost here.

2. Step 2: Identify correct formula structure

   Number_of_layers should multiply Cost_per_layer first, then complexity can be considered separately.

3. Final Answer:

   The formula should multiply Number_of_layers by Cost_per_layer first -> Option D

4. Quick Check:

   Cost = layers x cost per layer first [OK]

Hint: Multiply layers by cost per layer before adding complexity [OK]

Common Mistakes:

• Ignoring operator precedence
• Including complexity directly in cost without context
• Using addition instead of multiplication

5.

You have two PCB design options:

• Option 1: 5 layers, $12 per layer, complexity score 4
• Option 2: 3 layers, $15 per layer, complexity score 6

If your goal is to minimize cost but keep complexity score under 5, which option should you choose?

hard

A. Option 2 because total cost is $45 which is cheaper

B. Option 2 because it has fewer layers even though complexity is higher

C. Option 1 because total cost is $60 and complexity is acceptable

D. Neither option because both exceed complexity limits

Solution

1. Step 1: Calculate total cost for both options

   Option 1: 5 x $12 = $60; Option 2: 3 x $15 = $45.

2. Step 2: Check complexity scores against limit

   Option 1 complexity = 4 (under 5), Option 2 complexity = 6 (exceeds 5).

3. Step 3: Choose option meeting complexity and cost goals

   Option 1 meets complexity limit and is acceptable cost; Option 2 is cheaper but complexity too high.

4. Final Answer:

   Option 1 because total cost is $60 and complexity is acceptable -> Option C

5. Quick Check:

   Cost and complexity balance = Option 1 [OK]

Hint: Check complexity limit first, then compare costs [OK]

Common Mistakes:

• Choosing cheapest without checking complexity
• Ignoring complexity limits
• Miscalculating total cost