N = 2 · Server VRM · native SPICE

TI PMP21872-class 12 V → 1 V / 40 A · two 400 kHz buck phases · independent SPICE fixed-phase sweep + 10 ms transient
R6 · NATIVE NGSPICE ONLYPRESCRIBED PHASE COMMAND
0.00 ms

Vout · absolute native SPICE voltage

3.0–4.8 ms transition · 18% span
Drag plot to zoom · wheel to zoom · double-click reset
Measured Vout min–max · native display binsControl enabled · 3.0 msEnd of phase transition · 4.8 ms
Initial RMS —Final RMS —RMS reduction —Mean Vout (after) —

Ripple profile vs. relative phase

Native ngspice fixed-phase sweeps · 15° steps
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Independent native SPICE phase sweepCurrent phase marker

Phase circle · relative position

Stroboscopic view
0°90°180°270°0.0°Δφ₂₁● phase 1: 0°● phase 2: variable

Relative phase · measured from SPICE gate edges

Gate-derived phase difference · programmed timing

Vout switching-cycle RMS

Every 2.5 µs cycle · computed from SPICE Vout

Vout before · 2.700–2.740 ms

native SPICE · absolute volts

Vout after · 8.000–8.040 ms

native SPICE · absolute volts

Gate pulses

VGH1 / VGH2

Inductor currents

iL1 / iL2

Switch-node voltages

Vsw1 / Vsw2
12 V input · 1 V/40 A nominal · open-loop D=0.086 · 2 × 400 kHz · L = 200 nH/phase · C = 1500 µF · ESR = 0.45 mΩ · Rload = 25 mΩ. Idealized native switch and parasitic assumptions, not exact TI BOM.All plotted electrical quantities originate from saved native ngspice files. No new SPICE runs are executed in this rebuild.