Mounting hole placement in PCB Design - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding Mounting Hole Placement Importance

Why is precise mounting hole placement critical in PCB design?

A To ensure the PCB fits correctly in the enclosure and avoids mechanical stress

B To increase the electrical conductivity of the PCB

C To reduce the number of components on the PCB

D To improve the thermal performance of the PCB

💡 Hint

Think about the physical fit and mechanical stability of the PCB.

Mounting holes must be placed accurately to ensure the PCB fits properly in its enclosure and to prevent mechanical stress that could damage components or the board itself.

❓ data_modeling

intermediate

Calculating Mounting Hole Coordinates

You have a rectangular PCB of 100mm width and 80mm height. Mounting holes should be placed 5mm from each edge. What are the X and Y coordinates of the top-left mounting hole assuming origin (0,0) is at the bottom-left corner?

A (5, 75)

B (5, 5)

C (95, 75)

D (95, 5)

💡 Hint

Remember the origin is bottom-left, so Y increases upwards.

The top-left hole is 5mm from the left edge (X=5) and 5mm from the top edge (Y=80-5=75).

❓ dax_lod_result

advanced

DAX Measure for Counting Mounting Holes by Type

Given a table 'MountingHoles' with columns 'HoleType' and 'Diameter', which DAX measure correctly counts the number of mounting holes with diameter greater than 3mm?

PCB Design

Measure = CALCULATE(COUNTROWS(MountingHoles), FILTER(MountingHoles, MountingHoles[Diameter] > 3))

A Measure = SUMX(MountingHoles, IF(MountingHoles[Diameter] > 3, 1, 0))

B Measure = COUNTROWS(FILTER(MountingHoles, MountingHoles[Diameter] > 3))

C Measure = COUNT(MountingHoles[Diameter] > 3)

D Measure = CALCULATE(COUNTROWS(MountingHoles), FILTER(MountingHoles, MountingHoles[Diameter] > 3))

💡 Hint

Consider the correct use of CALCULATE and FILTER functions in DAX.

Option D uses CALCULATE with FILTER correctly to count rows where Diameter is greater than 3mm.

❓ visualization

advanced

Best Visualization for Mounting Hole Distribution

Which visualization best shows the spatial distribution of mounting holes on a PCB layout?

A Bar chart showing count of holes by diameter

B Pie chart showing percentage of hole types

C Scatter plot with X and Y coordinates of holes

D Line chart showing hole diameter over time

💡 Hint

Think about showing positions on a 2D plane.

A scatter plot with X and Y coordinates effectively shows where holes are placed on the PCB.

🔧 Formula Fix

expert

Debugging Mounting Hole Placement Calculation

Given this SQL snippet to select mounting holes within 5mm of PCB edges (width=100, height=80):

SELECT * FROM Holes WHERE X < 5 OR X > 95 OR Y < 5 OR Y > 75;

Which issue will cause incorrect results?

A Coordinates comparison values are off by 1mm

B Strict inequalities (<, >) exclude holes exactly at 5mm or 95mm

C Using OR instead of AND causes holes not near edges to be included

D The query should use BETWEEN instead of inequalities

💡 Hint

Consider if holes exactly at 5mm from edges should be included using the given inequalities.

The query uses strict inequalities (< 5, > 95, < 5, > 75), which exclude holes positioned exactly 5mm from the edges (e.g., X=5, X=95, Y=5, Y=75), typical for mounting holes.