PCB Design - Advanced Routing Techniques
A PCB designer wrote the formula Z0 = (87 / sqrt(Er + 1.41)) * ln(5.98 * H / (0.8 * W - T)) but the impedance values are incorrect. What is the likely error?
A PCB designer wrote the formula Z0 = (87 / sqrt(Er + 1.41)) * ln(5.98 * H / (0.8 * W - T)) but the impedance values are incorrect. What is the likely error?
medium📝 Formula Fix Q6 of 15
Step-by-Step Solution
Solution:
Step 1: Identify formula error
The denominator should be (0.8 * W + T), not (0.8 * W - T).Step 2: Understand impact of subtraction
Subtraction reduces denominator, inflating ln value and causing wrong impedance results.Final Answer:
Using subtraction instead of addition in denominator -> Option BQuick Check:
Denominator sign error = Wrong impedance [OK]
Quick Trick: Use plus sign in denominator, not minus [OK]
Common Mistakes:
MISTAKES- Confusing addition and subtraction in formula
- Changing constants without reason
- Using wrong logarithm base
Master "Advanced Routing Techniques" in PCB Design
Want More Practice?
15+ quiz questions · All difficulty levels · Free
Free Signup - Practice All QuestionsMore PCB Design Quizzes