Lime Microsystems LMS7002MR3 - 5 Calibration Algorithms; A3.1 VCO Coarse Tuning

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Calibration algorithms
A3.1 VCO coarse tuning
This chapter describes the algorithm for VCO coarse tuning, which finds the optimum
SWC_VCO[7:0] value.
VCO coarse tuning algorithm goes through 3 following phases:
1. Initialization: sets the static control words for the synthesizer
2. Decision: monitors the two digital outputs from the synthesizer
(COARSE_STEPDONE and COARSE_COMPO) and makes a decision on the correct
value of every bit of SWC_VCO[7:0]. Input control bit of COARSE_START will be
used to start each cycle.
3. Normal mode setting: controls are set back to the values needed for normal synthesizer
operation.
Below are two similar algorithms, one for the SXT/SXR and other CGEN. Algorithms differ
mainly in the configuration register addresses.