analog-hardmacro-gen

Analog Hardmacro Gen

Takes a verified analog block (SPICE corner sweep passed, optionally hardware-verified) and produces the four deliverables that digital PnR (OpenROAD) needs to integrate it alongside standard cells.

When to use

• Step A7 of the analog track
• After analog-extraction-resim confirms post-layout specs are acceptable
• When the user says "package this analog block for digital integration"

Inputs

1. analog/<block>/corner_results.json — worst-case timing from SPICE
2. analog/<block>/layout.mag — Magic layout (or generate via eda_analog_layout)
3. analog/<block>/spec.json — port definitions
4. PDK (gf180 or sky130)

Four deliverables

Deliverable PRESENCE + non-degeneracy is enforced deterministically: programs/analog_hardmacro_check.py (all 4 files exist; LEF has MACRO/PIN, LIB has cell, V has module) and programs/analog_liberty_nonzero_delay_check.py (the "no zero-delay Liberty" rule — area-only / all-zero .lib => FAIL). Cross-file pin-name equality is enforced by programs/analog_hardmacro_pinname_consistency_check.py.

1. GDS (hardmacro/<block>/<block>.gds)

• Source: Magic layout → eda_gds or eda_run_tcl with Magic gds write
• The gds write / lef write Magic TCL is a fixed command template — emitted deterministically alongside the port-extraction TCL in programs/magic_port_extract_emit.py.
• Must include all metal layers, vias, device layers

2. LEF abstract (hardmacro/<block>/<block>.lef)

• Generated via Magic lef write (see magic_port_extract_emit.py)
• Contains: MACRO definition, PIN locations (with DIRECTION + USE), OBS layer, SIZE
• Pin names must match the RTL port names exactly — enforced by programs/analog_hardmacro_pinname_consistency_check.py (3-way set-equality: spec.json interface.pins ↔ LEF PINs ↔ Verilog ports; portless LEF + ported Verilog => FAIL).

3. Liberty timing model (hardmacro/<block>/<block>.lib)

• Derived from SPICE corner results (worst-case SS corner).
• Non-degeneracy enforced by programs/analog_liberty_nonzero_delay_check.py: the .lib must carry at least one timing/leakage attribute and every timing value must be non-zero (an area-only or all-zero .lib is the documented vacuous-STA defect and FAILs). The check also reports the corner-sweep provenance (real_ngspice vs stub) read from corner_results.json.
• Judgment residual (NOT a program): which arcs to model and what delay value to assign — corner_results.json carries the analog spec value (e.g. vout_v, ota_ugbw_hz) per PVT corner, NOT pre-computed cell_rise/cell_fall/setup/hold/leakage timing arcs. Mapping a measured analog metric onto Liberty timing arcs for a given control interface is an analog-modeling decision; only the SS-worst-corner selection and the non-zero formatting are deterministic.

4. Behavioral Verilog (hardmacro/<block>/<block>.v)

• For gate-level simulation (digital TB can instantiate this)
• The port list must match the spec interface — enforced by programs/analog_hardmacro_pinname_consistency_check.py.
• Judgment residual (NOT a program): HOW MUCH analog behavior to model in the integration Verilog — which ports matter for digital sim, what minimal behavior keeps gate-level sim meaningful:

  module ldo_1v8 (input vin, input en, input [2:0] trim, output vout);
    assign vout = en ? 1'b1 : 1'bz;  // simplified: high when enabled
  endmodule
  

• Real analog behavior is in SPICE; this is just for digital integration sim

Workflow

1. GDS: If layout.mag exists, run Magic gds write (template via magic_port_extract_emit.py); else run eda_analog_layout first
2. LEF: Run Magic lef write with correct pin definitions
3. Liberty: Pick the SS (worst) corner from corner_results.json and author the .lib with non-zero arcs (modeling judgment per § 3 above); non-degeneracy gate = analog_liberty_nonzero_delay_check.py
4. Behavioral Verilog: Emit a module whose port list matches spec.json interface.pins; behavior-modeling is judgment (§ 4 above)
5. Validate (deterministic, do not hand-check): run analog_hardmacro_check.py + analog_hardmacro_pinname_consistency_check.py
   • analog_liberty_nonzero_delay_check.py on the project dir

Output format

hardmacro/<block>/
  ├── <block>.gds      — physical layout
  ├── <block>.lef      — abstract for PnR placement
  ├── <block>.lib      — timing model for STA
  └── <block>.v        — behavioral model for simulation

Do not

• Do not generate Liberty with zero delays — use actual SPICE-measured values (enforced by programs/analog_liberty_nonzero_delay_check.py)
• Do not mismatch pin names between LEF and Verilog — causes LVS failure at integration (enforced by programs/analog_hardmacro_pinname_consistency_check.py)
• Do not include internal device-level detail in LEF — only pins and obstruction (modeling judgment, left to the agent)

Handoff

• hardmacro/<block>/ → Digital Step 15 (Floorplan; was Step 14 pre-Wave-91) via OpenROAD macro placement
• LEF → eda_pnr additional_lefs parameter
• Liberty → eda_sta additional liberty path
• Behavioral Verilog → eda_simulate for mixed-signal gate-level sim

Compliance gate (mandatory)

After producing your output, save it to a file and run:

python3 plugins/vibe-ic/_shared/skill_compliance_check.py \
    --requirements plugins/vibe-ic/skills/analog-hardmacro-gen/compliance.yaml \
    <your_output_file>

Exit 0 = PASS, exit 1 = FAIL with specific missing elements listed.

Your task is not complete until the audit returns PASS.