{
  "backend": "ltspice",
  "checks_skipped": [],
  "circuit": {
    "components": [
      {
        "ref": "V1",
        "type": "voltage",
        "value": "15"
      },
      {
        "ref": "R1",
        "type": "res",
        "value": "1.8k"
      },
      {
        "part": "DZ8V3",
        "ref": "D1",
        "type": "zener"
      },
      {
        "part": "QNPN_BF100",
        "ref": "Q1",
        "type": "npn"
      },
      {
        "ref": "RL",
        "type": "res",
        "value": "2k"
      }
    ],
    "directives": [
      ".model DZ8V3 D(BV=8.3 IBV=5m)",
      ".model QNPN_BF100 NPN(BF=100)"
    ],
    "nets": {
      "0": [
        "V1.-",
        "D1.anode",
        "RL.b"
      ],
      "vb": [
        "R1.b",
        "D1.cathode",
        "Q1.B"
      ],
      "vin": [
        "V1.+",
        "R1.a",
        "Q1.C"
      ],
      "vout": [
        "Q1.E",
        "RL.a"
      ]
    }
  },
  "deliverables": [
    {
      "kind": "ltspice-schematic",
      "path": "exp02-series-regulator.asc",
      "sha256": "b7fdaf0f7ffa84233f0b82ca47260fc8dfe433968cf6a2cc210ae5ac7baccbce",
      "unverified_reason": null,
      "verified": true,
      "verified_by": "emitted from the same circuit description that was simulated, and round-trips through the geometric parser. The exact bytes were not the ones handed to LTspice: the deliverable carries every run, with one active and the rest commented"
    }
  ],
  "design_notes": [],
  "designed_values": [],
  "devices": {
    "D1": {
      "directive": ".model DZ8V3 D(BV=8.3 IBV=5m)",
      "part": "DZ8V3",
      "policy": "synthesized",
      "report": "using a synthesised model: Vz=8.3 V anchored at a 5m test current, because the question specifies exactly 8.3 V and a nearby real part would answer a slightly different question"
    },
    "Q1": {
      "directive": ".model QNPN_BF100 NPN(BF=100)",
      "part": "QNPN_BF100",
      "policy": "synthesized",
      "report": "using a synthesised NPN(BF=100) model, the parameters the question specifies"
    }
  },
  "generated": "2026-08-25",
  "manifest_version": 1,
  "plan": {
    "measurements": [
      {
        "expr": "V(vout)",
        "name": "vout_nominal",
        "run": "nominal"
      },
      {
        "expr": "V(vb)",
        "guard": "cross-simulator tripwire: vb must sit near 8.292 V on any compliant backend",
        "name": "vb_nominal",
        "run": "nominal"
      },
      {
        "expr": "I(D1)",
        "name": "iz_nominal",
        "run": "nominal"
      },
      {
        "at": {
          "V1": 12
        },
        "expr": "V(vout)",
        "name": "vout_low",
        "run": "linesweep"
      },
      {
        "at": {
          "V1": 20
        },
        "expr": "V(vout)",
        "name": "vout_high",
        "run": "linesweep"
      },
      {
        "definition": "12 V to 20 V input, normalised to the 12 V output",
        "formula": "100 * (vout_high - vout_low) / vout_low",
        "kind": "derived",
        "name": "line_reg_pct"
      },
      {
        "at": {
          "RL": "100k"
        },
        "expr": "V(vout)",
        "name": "vout_noload",
        "run": "loadsweep"
      },
      {
        "at": {
          "RL": "500"
        },
        "expr": "V(vout)",
        "name": "vout_fullload",
        "run": "loadsweep"
      },
      {
        "definition": "no-load to full-load, normalised to full-load",
        "formula": "100 * (vout_noload - vout_fullload) / vout_fullload",
        "kind": "derived",
        "name": "load_reg_pct"
      },
      {
        "assert": "zener_in_breakdown",
        "device": "D1",
        "kind": "regime",
        "run": "nominal",
        "vz": 8.3
      },
      {
        "assert": "bjt_active",
        "device": "Q1",
        "kind": "regime",
        "run": "nominal"
      },
      {
        "assert": "zener_in_breakdown",
        "device": "D1",
        "kind": "regime",
        "run": "linesweep",
        "vz": 8.3
      },
      {
        "assert": "bjt_active",
        "device": "Q1",
        "kind": "regime",
        "run": "linesweep"
      },
      {
        "assert": "zener_in_breakdown",
        "device": "D1",
        "kind": "regime",
        "run": "loadsweep",
        "vz": 8.3
      },
      {
        "assert": "bjt_active",
        "device": "Q1",
        "kind": "regime",
        "run": "loadsweep"
      }
    ],
    "runs": [
      {
        "id": "nominal",
        "type": "op"
      },
      {
        "id": "linesweep",
        "label": "line regulation",
        "sweep": {
          "source": "V1",
          "start": 12,
          "step": 1,
          "stop": 20
        },
        "type": "dc"
      },
      {
        "component": "RL",
        "id": "loadsweep",
        "label": "load regulation",
        "type": "param_sweep",
        "values": [
          "100k",
          "5k",
          "2k",
          "1k",
          "500"
        ]
      }
    ]
  },
  "prose": [],
  "question": {
    "asks": [
      {
        "answered_by": "vout_nominal",
        "text": "output voltage"
      },
      {
        "answered_by": "line_reg_pct",
        "text": "line regulation"
      },
      {
        "answered_by": "load_reg_pct",
        "text": "load regulation"
      },
      {
        "answered_by": "iz_nominal",
        "text": "Zener diode current"
      }
    ],
    "source": {
      "extractor": "human transcription from screenshot",
      "file": "lab manual, section 2.14 open ended question (screenshot, circuit diagram in image)"
    },
    "text": "Calculate the output voltage in both load and line regulation and Zener diode current in the regulator circuit shown below using LTspice."
  },
  "question_id": "exp02-series-regulator",
  "regime_checks": [
    {
      "assertion": "zener_in_breakdown",
      "device": "D1",
      "examined": "I(D1) against a 0.0001 A minimum reverse current, and its terminal voltage against Vz=8.3 V, at 1 operating point of run 'nominal'",
      "held": true,
      "reasons": [],
      "run": "nominal"
    },
    {
      "assertion": "bjt_active",
      "device": "Q1",
      "examined": "Vce of Q1 against 0.2 V, and Ib for cut-off, at 1 operating point of run 'nominal'",
      "held": true,
      "reasons": [],
      "run": "nominal"
    },
    {
      "assertion": "zener_in_breakdown",
      "device": "D1",
      "examined": "I(D1) against a 0.0001 A minimum reverse current, and its terminal voltage against Vz=8.3 V, at 9 sweep points of run 'linesweep'",
      "held": true,
      "reasons": [],
      "run": "linesweep"
    },
    {
      "assertion": "bjt_active",
      "device": "Q1",
      "examined": "Vce of Q1 against 0.2 V, and Ib for cut-off, at 9 sweep points of run 'linesweep'",
      "held": true,
      "reasons": [],
      "run": "linesweep"
    },
    {
      "assertion": "zener_in_breakdown",
      "device": "D1",
      "examined": "I(D1) against a 0.0001 A minimum reverse current, and its terminal voltage against Vz=8.3 V, at 5 sweep points of run 'loadsweep'",
      "held": true,
      "reasons": [],
      "run": "loadsweep"
    },
    {
      "assertion": "bjt_active",
      "device": "Q1",
      "examined": "Vce of Q1 against 0.2 V, and Ib for cut-off, at 5 sweep points of run 'loadsweep'",
      "held": true,
      "reasons": [],
      "run": "loadsweep"
    }
  ],
  "results": [
    {
      "backend": "ltspice",
      "name": "vout_nominal",
      "reliable": true,
      "run": "nominal",
      "source": "simulation",
      "value": 7.48403263092041,
      "verification": "external",
      "warnings": []
    },
    {
      "backend": "ltspice",
      "name": "vb_nominal",
      "reliable": true,
      "run": "nominal",
      "source": "simulation",
      "value": 8.292138713092461,
      "verification": "external",
      "warnings": []
    },
    {
      "backend": "ltspice",
      "name": "iz_nominal",
      "reliable": true,
      "run": "nominal",
      "source": "simulation",
      "value": -0.0036895410157740116,
      "verification": "external",
      "warnings": []
    },
    {
      "at": {
        "V1": 12
      },
      "backend": "ltspice",
      "name": "vout_low",
      "reliable": true,
      "run": "linesweep",
      "source": "simulation",
      "value": 7.46865177154541,
      "verification": "external",
      "warnings": []
    },
    {
      "at": {
        "V1": 20
      },
      "backend": "ltspice",
      "name": "vout_high",
      "reliable": true,
      "run": "linesweep",
      "source": "simulation",
      "value": 7.498468399047852,
      "verification": "external",
      "warnings": []
    },
    {
      "backend": "ltspice",
      "definition": "12 V to 20 V input, normalised to the 12 V output",
      "formula": "100 * (vout_high - vout_low) / vout_low",
      "name": "line_reg_pct",
      "reliable": true,
      "run": null,
      "source": "derived",
      "value": 0.39922369410820396,
      "verification": "external",
      "warnings": []
    },
    {
      "at": {
        "RL": "100k"
      },
      "backend": "ltspice",
      "name": "vout_noload",
      "reliable": true,
      "run": "loadsweep",
      "source": "simulation",
      "value": 7.585122108459473,
      "verification": "external",
      "warnings": []
    },
    {
      "at": {
        "RL": "500"
      },
      "backend": "ltspice",
      "name": "vout_fullload",
      "reliable": true,
      "run": "loadsweep",
      "source": "simulation",
      "value": 7.447519779205322,
      "verification": "external",
      "warnings": []
    },
    {
      "backend": "ltspice",
      "definition": "no-load to full-load, normalised to full-load",
      "formula": "100 * (vout_noload - vout_fullload) / vout_fullload",
      "name": "load_reg_pct",
      "reliable": true,
      "run": null,
      "source": "derived",
      "value": 1.8476262344191192,
      "verification": "external",
      "warnings": []
    }
  ],
  "warnings": []
}