Adom Fields

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@@ -0,0 +1,62 @@+[+ {+  "t": 0,+  "title": "Current density"+ },+ {+  "t": 20,+  "title": "Heat flow"+ },+ {+  "t": 32,+  "title": "Temperature"+ },+ {+  "t": 43,+  "title": "Flow"+ },+ {+  "t": 56,+  "title": "River: voltage as water"+ },+ {+  "t": 70,+  "title": "Energy: it flows in the fields"+ },+ {+  "t": 85,+  "title": "Light: how fast a change travels"+ },+ {+  "t": 100,+  "title": "The energy cycle of a buck"+ },+ {+  "t": 114,+  "title": "Charge: the board as capacitors"+ },+ {+  "t": 128,+  "title": "Magnetic field"+ },+ {+  "t": 141,+  "title": "EMC screen"+ },+ {+  "t": 155,+  "title": "Ground and return paths"+ },+ {+  "t": 167,+  "title": "Noise: plane resonance and crosstalk"+ },+ {+  "t": 180,+  "title": "Power delivery (PDN)"+ },+ {+  "t": 193,+  "title": "Signals: copper as capacitors"+ }+]\ No newline at end of file

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@@ -0,0 +1,52 @@+WEBVTT++00:00:00.000 --> 00:00:05.664+Adom Fields: every field on your board, solved from the board file and shown in 3D.++00:00:06.714 --> 00:00:20.322+Current density: amps through every square millimetre of copper, solved on the real board. Yellow is where the current crowds; the busiest spot here, the switch node, runs about 46 amps per square millimetre.++00:00:21.422 --> 00:00:31.838+Heat flow: where the watts travel away from the hot parts. U1 puts out a quarter watt; about half spreads along its copper and almost a third drops down its three vias.++00:00:32.938 --> 00:00:43.090+Temperature rise over the whole board, in still or moving air. U1 is the hottest part, 46 degrees above the room, against a 55 degree budget.++00:00:44.190 --> 00:00:56.406+The Flow view: every particle is current, moving from plus to minus, faster where the copper is busier. At each via, the share of particles that drop through is the share of current it carries.++00:00:57.506 --> 00:01:10.130+The River view: the circuit as water. Height is voltage, so twelve volts is a plateau, five volts a terrace, and ground the sea. Loads are waterfalls, and the switch node rises and falls like a tide.++00:01:11.230 --> 00:01:25.198+The Energy view. The energy is not in the copper: it travels through the board between the layers, in the electric and magnetic fields. The electrons crawl at a millimetre a second; the energy moves at half the speed of light.++00:01:26.298 --> 00:01:40.290+The Light view: how fast a change travels, as a share of the speed of light. A switch-on wave crosses this board in about 166 picoseconds, slowed down billions of times so you can watch it arrive at each part.++00:01:41.390 --> 00:01:54.542+One switching cycle of the buck, slowed a million times. Energy leaves the input capacitors, flows through U1 into the inductor's magnetic field, then that field collapses and keeps pushing current to the load.++00:01:55.642 --> 00:02:07.810+The Charge view: wherever copper at two voltages faces across the board, it stores charge like a capacitor. The switch node blinks as it charges and empties five hundred thousand times a second.++00:02:08.910 --> 00:02:21.270+The Magnetic view: every current wraps itself in a field, and the sheet above the board is what a near-field probe would see. The strongest spot, near the inductor, is about the Earth's own field.++00:02:22.370 --> 00:02:35.378+The EMC screen: the red patch is the hot loop, the switching current's path, and its area acts like an antenna. The chart estimates the radiated noise at three metres against the FCC class B limit.++00:02:36.478 --> 00:02:46.918+The Ground view: ground is copper too, so returning current lifts it by millivolts. Connectors whose cables could meet off the board are drawn as possible ground loops.++00:02:48.018 --> 00:02:59.850+The Noise view: every power pour over ground is a cavity that rings like a drum. Here the first mode sits far above the converter's harmonics, and the crosstalk onto quiet nets stays under budget.++00:03:00.950 --> 00:03:12.758+Power delivery: how stiff each rail is from slow changes to fast ones. Each column is one part's share of the current; red over the rim means the rail's impedance misses its target.++00:03:13.858 --> 00:03:27.418+Signals: copper facing copper across the board is a capacitor. On this motor controller, the battery rail over ground makes about 144 picofarads, a little free decoupling at high frequency.++00:03:27.718 --> 00:03:39.334+That's every view. Your AI plans the inputs, Adom Fields does the deterministic solve, and every finding comes back with its fix. Get it free on the Adom wiki, at adom.inc.