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32
SNAU076B
LMK04800 Family
Revised - August 2014
Copyright © 2014, Texas Instruments Incorporated
PLL2 Tab
Figure 12: PLL2 tab
The PLL2 tab allows the user to change the following parameters in Table 9.
Table 9: Registers Controls and Descriptions in PLL2 tab
Control Name
Register Name
Description
Reference Oscillator
Frequency (MHz)
OSCin_FREQ
OSCin frequency from the External VCXO
or Crystal.
Phase Detector Frequency
(MHz)
n/s
PLL2 Phase Detector Frequency (PDF).
This value is calculated as:
PLL2 PDF = OSCin Frequency
*(2
EN_PLL2_REF_2X
) / PLL2_R.
VCO Frequency (MHz)
n/a
Internal VCO Frequency should be within
the allowable range of the LMK048xxB
device.
This value is calculated as:
VCO Frequency = PLL2 PDF * (PLL2_N *
PLL2_P * VCO divider value).
Doubler
EN_PLL2_REF_2X
PLL2 Doubler.
0 = Bypass Doubler
1 = Enable Doubler
R Counter
PLL2_R
PLL2 R Counter value (1 to 4095).
N Counter
PLL2_N
PLL2 N Counter value (1 to 262143).
PLLN Prescaler
PLL2_P
PLL2 N Prescaler value (2 to 8).