Texas Instruments High Performance Frequency Synthesizer System with Integrated VCO LMX25313010EVAL/NOPB LMX25313010EVAL/NOPB 데이터 시트

제품 코드
LMX25313010EVAL/NOPB
다운로드
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Far-out Phase noise is worse than evaluation board instructions 
show 
•  Ensure the measurement equipment noise floor is not limiting the measurement.  For 
spectrum analyzers, the noise floor at a particular setting can be measured by removing the 
RF input signal 
•  If the settings are changed from what the board was designed for, ensure the delta-sigma 
modulator is not increasing the far-out noise.  To determine this, tune to an integer channel 
and set the ORDER bit to “Reset Modulator”.  The far out phase noise should not decrease.  If 
it does, try a loop filter with more attenuation or select a lower order delta-sigma modulator. 
 
Device Data 
The next few pages show data collected from the LMX2531LQ3010 evaluation board.