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RSFQ logic

Library cells (jtl, splitter, dff and five more) on the analytic SPICE engine and the served margin surrogate, then a composed circuit. The ground truth is JoSIM and the cell library is literature-reconstructed, not foundry GDS.
Each step is a CLI command and the same request with curl. The curl lines read $FLUXUS_API and $COGITAN_API_KEY; set them as in Getting started. The CLI runs the engine in-process and needs neither.

  1. Every cell's knobs

    The per-cell knob schema: units, ranges, defaults and ports.

    No CLI command; `fluxus capabilities` prints the sfq_predict card.

    curl
    curl -s "$FLUXUS_API/sfq/schema" -H "Authorization: Bearer $COGITAN_API_KEY"
    GET/v1/fluxus/sfq/schema

  2. Analytic SPICE margins for one cell

    Functional verdict, per-junction phase-slip counts and coarse bias/Ic margins.

    CLI
    fluxus spice --cell jtl --json
    curl
    curl -s "$FLUXUS_API/spice/cell" -H "Authorization: Bearer $COGITAN_API_KEY" \
  -H 'content-type: application/json' \
  -d '{"cell": "jtl"}'
    POST/v1/fluxus/spice/cellfluxus spice reference

  3. The served surrogate

    Functional verdict and margins from the fitted heads, with conformal bands, or a refusal.

    The CLI's `fluxus sfq` takes a netlist file and abstains on margins; margins are served for a named cell through the API.

    curl
    curl -s "$FLUXUS_API/sfq/predict" -H "Authorization: Bearer $COGITAN_API_KEY" \
  -H 'content-type: application/json' \
  -d '{"cell": "dff"}'
    POST/v1/fluxus/sfq/predict

  4. A one-call datasheet

    Margins, timing, yield and the surrogate check for one cell.

    No CLI command.

    curl
    curl -s "$FLUXUS_API/spice/characterize" -H "Authorization: Bearer $COGITAN_API_KEY" \
  -H 'content-type: application/json' \
  -d '{"cell": "jtl"}'
    POST/v1/fluxus/spice/characterize

  5. Export the netlist

    The JoSIM .cir deck for the cell and its experiment.

    No CLI command.

    curl
    curl -s "$FLUXUS_API/sfq/cir" -H "Authorization: Bearer $COGITAN_API_KEY" \
  -H 'content-type: application/json' \
  -d '{"cell": "jtl"}'
    POST/v1/fluxus/sfq/cir

  6. Check a netlist you hold

    Parse, design-rule and envelope checks on a .cir file. Margins abstain on this path: a bare netlist carries no spec knobs for the heads to read. Here the netlist is the library JTL.

    CLI
    fluxus sfq --cir jtl.cir --cell-type jtl --json
    curl
    curl -s "$FLUXUS_API/sfq/predict" -H "Authorization: Bearer $COGITAN_API_KEY" \
  -H 'content-type: application/json' \
  -d '{"cir": ".model jmitll jj(rtype=1, vg=2.8mV, cap=0.07pF, r0=160, rN=16, icrit=0.1mA)\nLIN in s1 2p\nB01 s1 g1 jmitll area=2.16\nLP01 g1 0 0.086p\nLRB01 g1 q1 0.086p\nRB01 q1 s1 5.23\nIB01 0 b1 pwl(0 0 50p 150u)\nLPR01 s1 b1 0.278p\nL01 s1 s2 2.425p\nB02 s2 g2 jmitll area=2.16\nLP02 g2 0 0.086p\nLRB02 g2 q2 0.086p\nRB02 q2 s2 5.23\nIB02 0 b2 pwl(0 0 50p 150u)\nLPR02 s2 b2 0.278p\nLOUT s2 out 2.031p\nROUT out 0 2\n"}'
    POST/v1/fluxus/sfq/predictfluxus sfq reference

  7. Compose and verify a circuit

    Three wired cells built into one netlist and verified end to end.

    No CLI command.

    curl
    curl -s "$FLUXUS_API/circuit/verify" -H "Authorization: Bearer $COGITAN_API_KEY" \
  -H 'content-type: application/json' \
  -d '{"cells": [{"id": "J1", "kind": "sfq", "name": "jtl", "params": {}}, {"id": "S1", "kind": "sfq", "name": "splitter", "params": {}}, {"id": "J2", "kind": "sfq", "name": "jtl", "params": {}}], "wires": [{"from": ["J1", "out"], "to": ["S1", "in"]}, {"from": ["S1", "outa"], "to": ["J2", "in"]}]}'
    POST/v1/fluxus/circuit/verify

  8. Timing of the circuit

    Analytic (nominal-inductance) timing of the same chain.

    No CLI command.

    curl
    curl -s "$FLUXUS_API/circuit/timing" -H "Authorization: Bearer $COGITAN_API_KEY" \
  -H 'content-type: application/json' \
  -d '{"cells": [{"id": "J1", "kind": "sfq", "name": "jtl", "params": {}}, {"id": "S1", "kind": "sfq", "name": "splitter", "params": {}}, {"id": "J2", "kind": "sfq", "name": "jtl", "params": {}}], "wires": [{"from": ["J1", "out"], "to": ["S1", "in"]}, {"from": ["S1", "outa"], "to": ["J2", "in"]}]}'
    POST/v1/fluxus/circuit/timing

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