Why design rules prevent manufacturing defects in PCB Design - Formula Trace Breakdown

Sample Data

Sample PCB design rules with their descriptions and the manufacturing defects they help prevent.

Cell	Value
A1	Design Rule
B1	Description
C1	Potential Defect Prevented
A2	Minimum Trace Width
B2	Ensures traces are thick enough to carry current
C2	Open circuits due to thin traces
A3	Minimum Spacing
B3	Keeps space between traces to avoid shorts
C3	Short circuits from overlapping traces
A4	Drill Hole Size
B4	Specifies hole size for vias and pads
C4	Misaligned or incomplete holes
A5	Solder Mask Clearance
B5	Prevents solder bridging between pads
C5	Solder shorts during assembly
A6	Component Placement Rules
B6	Ensures components fit and do not overlap
C6	Mechanical interference or assembly errors

Formula Trace

SUMPRODUCT(--(TraceWidth >= MinWidth), --(Spacing >= MinSpacing), --(DrillSize >= MinDrill), --(SolderMaskClearance >= MinClearance), --(ComponentPlacement = "Valid"))

Step 1: TraceWidth >= MinWidth

Step 2: Spacing >= MinSpacing

Step 3: DrillSize >= MinDrill

Step 4: SolderMaskClearance >= MinClearance

Step 5: ComponentPlacement = "Valid"

Step 6: --(TraceWidth >= MinWidth) * --(Spacing >= MinSpacing) * --(DrillSize >= MinDrill) * --(SolderMaskClearance >= MinClearance) * --(ComponentPlacement = "Valid")

Step 7: SUMPRODUCT(...)

Cell Reference Map

    A       B       C       D       E       F
1 | TraceW | Spacing | Drill  | SolderM | CompPl |
2 | 0.15   | 0.20    | 0.30   | 0.10    | Valid  |
3 | 0.10   | 0.10    | 0.30   | 0.10    | Valid  |
4 | 0.08   | 0.20    | 0.30   | 0.10    | Valid  |
5 | 0.15   | 0.20    | 0.25   | 0.10    | Valid  |
6 | 0.15   | 0.20    | 0.30   | 0.05    | Valid  |

The formula references columns for Trace Width, Spacing, Drill Size, Solder Mask Clearance, and Component Placement validity for multiple design items.

Result

    A       B       C       D       E       F       G
1 | TraceW | Spacing | Drill  | SolderM | CompPl | Valid |
2 | 0.15   | 0.20    | 0.30   | 0.10    | Valid  | 1     |
3 | 0.10   | 0.10    | 0.30   | 0.10    | Valid  | 0     |
4 | 0.08   | 0.20    | 0.30   | 0.10    | Valid  | 0     |
5 | 0.15   | 0.20    | 0.25   | 0.10    | Valid  | 0     |
6 | 0.15   | 0.20    | 0.30   | 0.05    | Valid  | 0     |
7 | Total compliant designs: 1                          |

The final column shows 1 for design items that meet all rules and 0 otherwise. The total compliant count is 1.

Sheet Trace Quiz - 3 Questions

Which design item failed the minimum spacing rule?

A Item 2

B Item 3

C Item 4

D Item 5

Key Result

SUMPRODUCT with logical tests converts TRUE/FALSE to 1/0 and sums fully compliant design items.