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THE FEUTEX TOOLKIT

Integer-N PLL Frequency Plan

Calculate phase-detector and synthesized output frequencies.

Communications workspace● Runs in your browser
01 Your input
02 Your result
View or copy raw result data
Formulafpfd=fref/R; fvco=Nfpfd; fout=fvco/D
Sources and model references

Worked example

Inputs

Reference frequency
10000000 Hz
Reference divider
10
Feedback divider
240
Output divider
2

Expected results

Phase-detector frequency
1000000 Hz
VCO frequency
240000000 Hz
Output frequency
120000000 Hz

Load the example in the workspace to reproduce these results. Display rounding does not change the underlying calculation.

How to use this tool

  1. Enter the labeled inputs in the indicated units.
  2. Calculate and compare every output against the stated model assumptions.

Try this example

{
  "ref": 10000000,
  "r": 10,
  "n": 240,
  "out": 2
}

Accuracy and scope

Integer dividers only; no VCO range, spurs or loop stability evaluation. Simplified analytical model; not a design recommendation or safety certification.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.