Texas Instruments High Performance Frequency Synthesizer System with Integrated VCO LMX25312820EVAL/NOPB LMX25312820EVAL/NOPB Datenbogen

Produktcode
LMX25312820EVAL/NOPB
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PLL/VCO 
 
 
 
The PLL/VCO tab shows all the important PLL controls.  Reference Oscillator 
should be programmed to the reference frequency connected to the OSCin of the 
evaluation board.  R Counter, Phase Detector Frequency, N Counter, and 
Charge Pump Gain should be set to provide the desired output frequency with an 
optimized loop filter.  The desired VCO frequency may also be entered directly 
into the VCO frequency box. 
 
The LMX2531 also has an output divider which can be enabled by change divide 
value from 1 to 2 by Fout frequency box.  Be sure to load the device (Ctrl+L) after 
changing this divider to allow the VCO to calibrate for optimal phase noise 
performance. 
 
 
 
 
 
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