Analog Integrate

analog-integrate

Architect Phase 3 -- integration verification. After all sub-blocks pass L2 transistor-level verification, this skill replaces behavioral models with verified netlists one by one, runs top-level integration checks at each step, and produces the final integration verifier-report.

Effort Gating

Corner matrix follows the same table as /analog-verify (see shared-references/effort-contract.md):

Print at startup:

Copy code
[effort: <level>] corners=<N>

Inputs

See shared-references/handoff-contracts.md section "Verified sub-blocks -> Architect (analog-integrate)" for the full handoff payload:

Outputs

The report includes per-spec results (measured / target / margin) for every top-level spec across all corners at the current effort level.

Integration Procedure

1. Replace Behavioral Models One by One

For each sub-block, in dependency order (inputs before outputs):

1. Replace blocks/<name>/behavioral.va with the verified blocks/<name>/circuit/<block>.scs in the system-level testbench.
2. Keep all other sub-blocks as behavioral models during this step.
3. Run top-level specs and verify no regression.
4. If a regression appears, the responsible sub-block is the one just replaced -- flag it immediately before proceeding.

This incremental approach isolates integration failures to specific sub-blocks.

2. Run Top-Level Specs at Each Replacement Step

At each step, simulate the top-level specs from spec.yml:

• Compare against targets with measured / target / margin reporting.
• Any FAIL at this stage means the replaced sub-block's transistor implementation does not match its behavioral contract -- investigate the interface.

3. Final All-Transistor Verification

After all behavioral models are replaced:

1. Run the complete top-level spec suite with all transistor-level netlists.
2. Run across the corner matrix determined by the current effort level.
3. Document all results in the integration verifier-report.md.

Failure Routing

When integration verification fails:

1. Identify the responsible sub-block or interface:

   • If failure appeared at a specific replacement step, that sub-block is suspect.
   • If failure appears only in the all-transistor run, it is likely an interface mismatch between adjacent blocks.

2. Send back to design loop:

   • Revise the interface constraints or sub-block spec as needed.
   • Dispatch the affected sub-block's designer with updated constraints.
   • The designer/verifier loop re-runs for that sub-block only.

3. Architectural failure: if multiple sub-blocks fail or the failure is systemic (e.g., power budget blown), escalate to /analog-decompose for architecture revision.

Sign-Off Gate

L3 PVT verification is required before delivery.

Before the design can be delivered or migrated to Virtuoso:

1. Dispatch verifier with level: L3 on the fully integrated design.
2. All top-level specs must pass across all corners defined in spec.yml.
3. If any corner fails:
   • Performance issue: return to designer for the affected sub-block.
   • Architectural issue: return to /analog-decompose.

Do not proceed to Virtuoso migration until L3 passes.

Virtuoso Migration

After L3 sign-off, dispatch the designer agent with a Virtuoso migration task:

1. Input: path to the verified integrated netlist.
2. Action: designer migrates the netlist to a Virtuoso cellview and runs LVS.
3. Server: use role_mapping.designer from servers.yml (designer has Virtuoso write access).

The designer uses the virtuoso skill for schematic entry and LVS verification.

Handoff Acceptance Criteria

Phase 3 is complete when (from prompts/architect-prompt.md):

• All behavioral models replaced with transistor-level netlists
• Top-level specs verified with all-transistor integration testbench
• Integration verifier-report.md written with per-spec margins

Lessons Learned

At project completion (after the sign-off gate passes), the architect reviews iteration-log.yml and writes the summary.lessons_learned section. This is a first-class activity, not an afterthought. Focus on insights that would change future designs:

• Specs where behavioral model prediction diverged significantly from transistor-level
• Budget allocations that were too tight or too generous
• Verification conditions that were repeatedly flagged as incorrect
• Corner-specific surprises (e.g., "SS corner offset 3x worse than TT prediction")
• Optimizer usage patterns (which blocks needed it, which didn't)

At exhaustive effort, the architect also writes a retrospective narrative: "What emerged that could not have been predicted?" This reflection captures tacit knowledge that structured logs cannot.

These lessons are the most valuable output of the entire flow -- they make the next project's architect smarter. At effort >= standard, consider pushing lessons to /analog-wiki via archive-project.

References

• prompts/architect-prompt.md -- Phase 3 section and Lessons Learned section
• shared-references/handoff-contracts.md -- handoff payload requirements
• shared-references/effort-contract.md -- corner matrix and effort dimensions