Signal Integrity - Impedance
Created: February 22, 2016 | Updated: April 11, 2017
| Applies to versions: 16.0, 16.1, 17.0 and 17.1
Now reading version 16.1. For the latest, read: Signal Integrity - Impedance for version 21
Rule category: Signal Integrity
Rule classification: Unary
Summary
This rule specifies the minimum and maximum net impedance allowed. Net impedance is a function of the conductor geometry and conductivity, the surrounding dielectric material (the board base material, multi-layer insulation, solder mask, etc) and the physical geometry of the board (distance to other conductors in the z-plane).
Constraints
Default constraints for the Impedance rule.
- Minimum (Ohms) - the value for the minimum permissible net impedance.
- Maximum (Ohms) - the value for the maximum permissible net impedance.
How Duplicate Rule Contentions are Resolved
All rules are resolved by the priority setting. The system goes through the rules from highest to lowest priority and picks the first one whose scope expression matches the object(s) being checked.
Rule Application
Batch DRC and during Signal Integrity analysis.