SoC Integration · All levels
Chip-Package I/O Co-design: Comparison Matrix
Comparison Matrix for Chip-Package I/O Co-design.
Comparison matrix
Bump and IO strategies trade SI/PI margin against routability.
+------------------+----------------+----------------+----------------+
| Approach | Strength | Weakness | Best when |
+------------------+----------------+----------------+----------------+
| Strict | predictable | slower early | new program |
| Balanced | practical | needs rigor | stable teams |
| Aggressive | fast | escape risk | late schedule |
| Re-architect | durable | expensive | recurring failures |
+------------------+----------------+----------------+----------------+When to choose each approach
Pick the approach based on residual silicon risk, not only schedule pressure.
Review traps
Policy-only arguments without artifact evidence
Unbounded waivers
Evidence comparison
INTEGRATION EVIDENCE MATRIX — Chip-Package I/O Co-design
+-------------------+------------------------+--------------------------+-------------------------+
| Evidence | Tells you | Does not prove | Next action |
+-------------------+------------------------+--------------------------+-------------------------+
| Manifest diff | baseline changed | root cause itself | isolate first delta |
| Domain trace | where behavior diverged| ownership accountability | map to contract owner |
| Signoff dashboard | closure posture | reproducibility quality | verify source artifacts |
| Bring-up logs | software-visible symptom| physical/timing cause | correlate with HW trace |
| Waiver register | accepted residual risk | technical closure | review expiry criteria |
+-------------------+------------------------+--------------------------+-------------------------+SoC deep dive
Package assumptions must be treated as first-class chip constraints.
Concept diagram
PACKAGE CO-DESIGN
die io <-> package routing <-> board constraintsMetric graph
PACKAGE RISK MIX
SI margin █████
power integrity ████
lane mapping ███Reports and artifacts
bump map revision log
SI/PI margin report
IO co-design checklist
package bring-up failures
Mini case study
Link degradation on product board came from package routing assumptions not reflected in pre-silicon model.
Debug branches
Compare package model versions
Audit lane mapping
Correlate SI/PI margins to failures
Senior review question
Ask: what baseline, owner, and artifact prove this topic is truly closed?
Key takeaways
State baseline manifest and owner with every closure metric.
Run cross-domain regression after every top-level fix.
Common pitfalls
Comparing results across different manifests.
Unowned issues slipping through review cycles.
Waiving risks without expiry and validation plan.
Principal SoC review addendum
I/O co-design aligns pad-ring, bump assignment, voltage domains, ESD, and board routing expectations as a single contract.
Metric: I/O timing closure against package constraints