Add DC-bias C_eff stima to derating and INFO when bulk C has no HF ceramic.

Keep both as labelled estimates: no Murata lot curve and no invented Z(f) target without f_sw. Co-authored-by: Cursor <cursoragent@cursor.com>
2026-09-10 22:23:05 +02:00
parent 4fca789517
commit 4403c38d96
11 changed files with 412 additions and 2 deletions
@@ -0,0 +1,93 @@
+"""HF coverage INFO when bulk C exists without a 100 nF-class ceramic."""
+
+from backend.pinscopex.hf_coverage_check import check_hf_decoupling_coverage
+from backend.pinscopex.models import (
+    CapacitorSpecs,
+    Component,
+    ComponentConstraints,
+    ComponentType,
+    DesignGraph,
+    Net,
+    NetType,
+    Pin,
+    PinConnection,
+)
+
+
+def _graph(components, nets):
+    net_objs = {
+        name: Net(
+            name=name, net_type=ntype,
+            pins=[PinConnection(component_ref=r, pin_number=str(p)) for r, p in conns],
+        )
+        for name, (ntype, conns) in nets.items()
+    }
+    return DesignGraph(components=components, nets=net_objs)
+
+
+def _ic():
+    return Component(
+        reference="U1", value="", footprint="",
+        component_type=ComponentType.IC, mpn="UTEST",
+        pins={"1": "3V3", "2": "GND"},
+    )
+
+
+def _cmap():
+    return {
+        "UTEST": ComponentConstraints(
+            mpn="UTEST",
+            pintable=[Pin(number=1, name="VDD"), Pin(number=2, name="GND")],
+            absolute_maximum_ratings=[], rules=[],
+        )
+    }
+
+
+def _cap(ref, farads, net="3V3"):
+    return Component(
+        reference=ref, value="", footprint="C_0603",
+        component_type=ComponentType.CAPACITOR, mpn=ref,
+        pins={"1": net, "2": "GND"},
+        specs=CapacitorSpecs(value_farads=farads, value_formatted="x"),
+    )
+
+
+def test_bulk_only_is_info_ps_esr_001():
+    g = _graph(
+        {"U1": _ic(), "C1": _cap("C1", 10e-6)},
+        {
+            "3V3": (NetType.POWER, [("U1", "1"), ("C1", "1")]),
+            "GND": (NetType.GROUND, [("U1", "2"), ("C1", "2")]),
+        },
+    )
+    findings = check_hf_decoupling_coverage(g, _cmap())
+    assert len(findings) == 1
+    assert findings[0].rule_id == "PS-ESR-001"
+    assert findings[0].status == "INFO"
+
+
+def test_bulk_plus_100n_is_silent():
+    g = _graph(
+        {"U1": _ic(), "C1": _cap("C1", 10e-6), "C2": _cap("C2", 100e-9)},
+        {
+            "3V3": (NetType.POWER, [("U1", "1"), ("C1", "1"), ("C2", "1")]),
+            "GND": (NetType.GROUND, [("U1", "2"), ("C1", "2"), ("C2", "2")]),
+        },
+    )
+    assert check_hf_decoupling_coverage(g, _cmap()) == []
+
+
+def test_unknown_cap_value_is_not_guessed():
+    c = Component(
+        reference="C1", value="", footprint="",
+        component_type=ComponentType.CAPACITOR, mpn="C1",
+        pins={"1": "3V3", "2": "GND"},
+    )
+    g = _graph(
+        {"U1": _ic(), "C1": c},
+        {
+            "3V3": (NetType.POWER, [("U1", "1"), ("C1", "1")]),
+            "GND": (NetType.GROUND, [("U1", "2"), ("C1", "2")]),
+        },
+    )
+    assert check_hf_decoupling_coverage(g, _cmap()) == []