Part Number: LMX2572
We've been successfully using this part for almost 2 years now. I am now interested in trying to speed up the calibration time. So I thought I'd give "Partial Assist" a try (section 18.104.22.168 in the datasheet). I have found experimentally that writing VCO_SEL r20[13:11] causes the rb_VCO_SEL r110[7:5] to be incorrect. Aka, I can only verify my partial assist settings if I don't write VCO_SEL. Is that expected? Is there some other write that's needed to make rb_VCO_SEL accurate assuming Partial Assist?
Without writing VCO_SEL, it looks like my calculations (table 135 plus eq5 and eq6) are pretty close to the "rb" values. So I'm not worried about the table or the calculations.
What is the VCO_SEL you have assigned and the read back VCO_SEL value? Is the desired VCO frequency located in the boundaries of two adjacent VCO core?
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