LMX25120967EVAL/NOPB National Semiconductor, LMX25120967EVAL/NOPB Datasheet - Page 6

• Manufacturer Part Number: LMX25120967EVAL/NOPB
• Description: EVALUATION BOARD FOR LMX25120967
• Manufacturer: National Semiconductor
• Series: PLLatinum™r

Specifications of LMX25120967EVAL/NOPB

• Main Purpose: Timing, Frequency Synthesizer
• Embedded: No
• Utilized Ic / Part: LMX2512
• Primary Attributes: Single Fractional-N and Integer-N PLL with VCO
• Secondary Attributes: 967MHz, CodeLoader Graphical User Interface
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: *LMX25120967EVAL; *LMX25120967EVAL/NOPB; LMX25120967EVAL

LMX2512LQ0967 EVALUATION BOARD OPERATING INSTRUCTIONS
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Evaluation Board and CodeLoader Configuration
4.1
CodeLoader Control Settings
Table 4.1.1 summarizes the settings of the programming registers used in creating the plots in
the following section. To aid in setting up the correct configuration, the Mode pull down menu
contains a default state for CodeLoader. The default mode will set the bits to a known working
state. Use this mode to reset the configuration of the registers. The LMX2502/12 datasheet
provides additional details about the controls.
Note on SPI_DEF control:
With SPI_DEF set to 1, the initial startup of the LMX2512LQ0967 requires only the Default words
(R0 – R3). After startup, only word R0 is required to change the RF frequency. Setting SPI_DEF
to 0 allows words R4 through R6 to be loaded into the registers.
The LMX2512LQ0967 operates using one of three default IF frequencies depending on the
application and frequency plan. With the SPI_DEF bit set to 1, the IF N and R counter values
from the IF PLL tab are ignored, and the appropriate default values are used based on the
selected reference (OSC_FREQ) and IF frequency (IF_FREQ) from the Bits/Pins tab. If a non-
default IF frequency is desired, the SPI_DEF bit must be set to 0 and the desired IF frequency
can be entered using the IF PLL tab.
Note on Reference Frequency Controls:
The Bits/Pins, RF PLL and IF PLL tabs contain reference oscillator controls. For SPI_DEF = 1,
the IF PLL uses the OSC_FREQ and IF_FREQ controls on the Bits/Pins tab to determine the
counter values. For SPI_DEF = 0, the IF PLL uses reference frequency control on the IF PLL tab
to determine the N counter values (IF_A, IF_B) based on the IF VCO frequency entered. The RF
PLL uses reference frequency control on the RF PLL tab to determine the N counter values
(RF_A, RF_B, RF_FN) based on the RF VCO frequency entered. These reference frequency
controls are independent, and to obtain predictable device behavior, set them to the same
reference frequency.
LMX2512LQ0967
February 21, 2003
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