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Adom Fields
Public Made by Adomby adom
Adom Fields: where the current and the heat go on your board.
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John Lauer
0.9.6: inputs a solve assumed (datasheet fields, spec patch), reflections and TDR
4271eae
adom-fields 0.9.6
- The inputs a solve assumed (
review.inputs).- What it lists: every default or estimate the results lean on, most important first, each with the part and MPN, the datasheet field that replaces it, the spec key, and what moves (with a sensitivity where one can be computed).
specPatch: the spec fragment for an AI to fill from the datasheets.- On the TPS54202 buck: 14 medium items (the capacitors' DC-bias capacitance, the electrolytic's ESR, U1's θJC, the laminate Dk, cable lengths, PDN load steps) and 4 low.
- Reflections and TDR (
review.reflections).- The model: each checked net's path from driver to receiver, its segments as lines with the cross-section solve's Z0 and delay, and its vias as pad capacitance.
- Two ngspice runs: a 50 Ω TDR profile, and the real driver's overshoot, ringing and series termination.
- Which nets: impedance targets, clocks, length groups, and spec
tdr. - On the ESC's SWD clock: 40 % overshoot with a 0.5 ns edge, so a 38 Ω series resistor goes at the MCU pin.
- Fix: impedance segments'
psPerMmis in ps/mm (it was a factor of 10⁶ off).
# adom-fields 0.9.6
- **The inputs a solve assumed (`review.inputs`).**
- **What it lists:** every default or estimate the results lean on, most important first, each with the part and MPN, the datasheet field that replaces it, the spec key, and what moves (with a sensitivity where one can be computed).
- **`specPatch`:** the spec fragment for an AI to fill from the datasheets.
- **On the TPS54202 buck:** 14 medium items (the capacitors' DC-bias capacitance, the electrolytic's ESR, U1's θJC, the laminate Dk, cable lengths, PDN load steps) and 4 low.
- **Reflections and TDR (`review.reflections`).**
- **The model:** each checked net's path from driver to receiver, its segments as lines with the cross-section solve's Z0 and delay, and its vias as pad capacitance.
- **Two ngspice runs:** a 50 Ω TDR profile, and the real driver's overshoot, ringing and series termination.
- **Which nets:** impedance targets, clocks, length groups, and spec `tdr`.
- **On the ESC's SWD clock:** 40 % overshoot with a 0.5 ns edge, so a 38 Ω series resistor goes at the MCU pin.
- **Fix:** impedance segments' `psPerMm` is in ps/mm (it was a factor of 10⁶ off).