PLL Phase Margin
Calculate loop phase margin from unwrapped open-loop phase at the unity-gain crossover frequency.
Description
Calculate loop phase margin from unwrapped open-loop phase at the unity-gain crossover frequency.
PLL Phase Margin: Calculate loop phase margin from unwrapped open-loop phase at the unity-gain crossover frequency.
When to use PLL Phase Margin
Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.
- Loop phase at 0 dB (°)
- Required number input.
How PLL Phase Margin works
Calculate loop phase margin from unwrapped open-loop phase at the unity-gain crossover frequency. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.1
- Phase margin (°)
- The resulting phase margin returned as a number.
Limitations and assumptions
- PLL bandwidth, margin, lock time, output frequency, spur, and integrated-jitter estimates depend on loop order, charge pump, divider values, oscillator gain, reference noise, nonlinear acquisition, and the exact phase-noise integration limits. Simplified linear models primarily describe locked small-signal behavior.
- Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.
Alternative or Complementary approaches
Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.
References
-
Phase-locked loop — Wikipedia contributors
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