From b28f97f3526859633fde603764b827389279d10f Mon Sep 17 00:00:00 2001
From: Denis Chevalier <perso@denischevalier.fr>
Date: Mon, 10 Aug 2026 22:32:38 +0200
Subject: extract figures in separate files

---
 charts/crosstalk-mathematical-model.typ | 63 +++++++++++++++++++++++++++++++++
 1 file changed, 63 insertions(+)
 create mode 100644 charts/crosstalk-mathematical-model.typ

(limited to 'charts/crosstalk-mathematical-model.typ')

diff --git a/charts/crosstalk-mathematical-model.typ b/charts/crosstalk-mathematical-model.typ
new file mode 100644
index 0000000..7701ed9
--- /dev/null
+++ b/charts/crosstalk-mathematical-model.typ
@@ -0,0 +1,63 @@
+#import "../lib/unify.typ": qty, unit
+#import "@preview/cetz:0.5.2"
+#import "@preview/cetz-plot:0.1.4": plot
+
+#figure(
+  cetz.canvas({
+    import cetz.draw: *
+
+    plot.plot(
+      size: (12, 6),
+      x-mode: "log",
+      x-label: [Frequency $f$ ($unit("Hz")$)],
+      y-label: [Coupled Voltage $V_"coupled"$ ($unit("mV")$)],
+      x-min: 10,
+      x-max: 100000,
+      y-min: 0.001,
+      y-max: 65,
+      x-grid: "minor",
+      y-grid: "minor",
+      {
+        // 20 kHz System Bandwidth limit vertical reference line
+        plot.add(
+          ((20000, 0.001), (20000, 100)),
+          style: (
+            stroke: (paint: luma(120), thickness: 0.8pt, dash: "dashed"),
+          ),
+          label: none,
+        )
+
+        // Unshielded PCB trace: C_mutual = 1 pF, Z_victim = 10 kOhm
+        plot.add(
+          style: (stroke: (dash: "solid")),
+          label: [Unshielded trace \
+            ($qty(1, "pF"), qty(10, "kilo ohm")$)],
+          domain: (10, 100000),
+          samples: 8000,
+          f => 2 * calc.pi * f * 1e-12 * 10000 * 10 * 1000, // in mV
+        )
+
+        // Low-impedance node: C_mutual = 1 pF, Z_victim = 1 kOhm
+        plot.add(
+          style: (stroke: (dash: "dashed")),
+          label: [Low-impedance node \
+            ($qty(1, "pF"), qty(1, "kilo ohm")$)],
+          domain: (10, 100000),
+          samples: 8000,
+          f => 2 * calc.pi * f * 1e-12 * 1000 * 10 * 1000, // in mV
+        )
+
+        // Guard trace shielding: C_mutual = 0.05 pF, Z_victim = 10 kOhm
+        plot.add(
+          style: (stroke: (dash: "dotted")),
+          label: [Guard trace shielded \
+            ($qty(0.05, "pF"), qty(10, "kilo ohm")$)],
+          domain: (10, 100000),
+          samples: 8000,
+          f => 2 * calc.pi * f * 0.05e-12 * 10000 * 10 * 1000, // in mV
+        )
+      },
+    )
+  }),
+  caption: [Capacitive crosstalk coupled voltage ($V_"coupled"$) vs. frequency across different PCB layout conditions, demonstrating the $qty(20, "decibel per decade")$ slope up to the $qty(20, "kHz")$ system bandwidth boundary],
+) <figure-crosstalk-mathematical-model>
-- 
cgit