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Output frequency LMX2582, TICS pro


I have a question about configuring LMX2582.
The chip is palced on the evaluation board ADC32RF80EVM and I try to get 3GHz from LMX2582 outputs.
His input frequency = 122.88MHz (get from LMK04828).
I used "Tics pro" and set such values:
Input chain: Doubler = x1, Pre-R=1, Multiplier=1, Post-R=1.
Feedback: Prescaler = 2, Ndivider = 24, Fnum = 53, Fden = 128.
F_VCO = 6000 MGz.
Outputs chain: SEG1 = /2, Channel Divider MUX = SEG1, Output MUX = CHDIV.
So RFOutA = 3000MHz.
BUT: instead of 3000M, RFOutA is about 3031M.
I attached file *.tcs for "TICS Pro", may be you can help me to set right registers values?(I changed extension as  the site refuse to attach *.tcs)



  • Nick,

    I looked at the fine and nothing seems wrong about the frequencies. You should change OUTx_PWR, but this would not cause your issue. I do wonder if this is related to the VCO calibration. I would try changing CAL_CLK_DIV from divide by 1 to divide by 8 to see if it is related to this.

    The VCO divides the frequency into 6 VCO cores and each core has 183 different bands. So if the VCO calibration gets off, that would be an issue.