Star vs bus power routing in PCB Design - Formula Comparison Trace

Sample Data

This data shows current and voltage drop values for different loads connected using star and bus power routing methods in a PCB design.

Cell	Value
A1	Node
B1	Current (A)
C1	Voltage Drop (V)
D1	Routing Type
A2	Power Source
B2	10
C2	0
D2	Star
A3	Load 1
B3	3
C3	0.1
D3	Star
A4	Load 2
B4	4
C4	0.15
D4	Star
A5	Load 3
B5	3
C5	0.12
D5	Star
A6	Bus Total
B6	10
C6	0.35
D6	Bus

Formula Trace

Total Voltage Drop Star = SUM(C3:C5) Total Voltage Drop Bus = C6

Step 1: SUM(C3:C5)

Step 2: 0.1 + 0.15 + 0.12

Step 3: Total Voltage Drop Bus = C6

Cell Reference Map

    A          B          C          D
1 | Node     | Current  | Voltage  | Routing
2 | Power    | 10       | 0.00     | Star
3 | Load 1   | 3        | 0.10     | Star
4 | Load 2   | 4        | 0.15     | Star
5 | Load 3   | 3        | 0.12     | Star
6 | Bus Total| 10       | 0.35     | Bus

References:
- Voltage drops C3, C4, C5 used for star sum
- Voltage drop C6 used for bus

Cells C3 to C5 provide voltage drops for star routing loads. Cell C6 provides voltage drop for bus routing total.

Result

    A          B          C          D
1 | Node     | Current  | Voltage  | Routing
2 | Power    | 10       | 0.00     | Star
3 | Load 1   | 3        | 0.10     | Star
4 | Load 2   | 4        | 0.15     | Star
5 | Load 3   | 3        | 0.12     | Star
6 | Bus Total| 10       | 0.35     | Bus
7 | Total Voltage Drop Star: 0.37 V
8 | Total Voltage Drop Bus: 0.35 V

The total voltage drop for star routing is 0.37 V, calculated by summing individual loads. The bus routing voltage drop is 0.35 V, shown directly. This helps compare power routing methods.

Sheet Trace Quiz - 3 Questions

What is the total voltage drop for star routing?

A 0.10 V

B 0.35 V

C 0.37 V

D 0.12 V

Key Result

Sum of individual load voltage drops for star routing vs direct total voltage drop for bus routing