Wideband Frequency Synthesizer with Integrated VCO - LMX2581

LMX2581 (ACTIVE)

Wideband Frequency Synthesizer with Integrated VCO

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  • LMX2531  -  Lowest Current Consumption

Description

The LMX2581 is an ultra low noise wideband frequency synthesizer which integrates a delta-sigma fractional N PLL, a VCO with fully integrated tank circuit, and an optional frequency divider. This device integrates several low-noise, high precision LDOs to provide superior supply noise immunity and more consistent performance. When combined with a high quality reference oscillator, the LMX2581 generates a very stable, ultra low noise signal. The internal VCO can be bypassed so that an external VCO can be used.

Features

  • GENERAL FEATURES
    • 50 – 3760 MHz Output Frequency
    • Low Voltage Logic Compatibility
    • Digital Lock Detect
    • 32 Pin QFN Package
  • HIGH PERFORMANCE PLL
    • Supports Integer and Fractional Modes
    • –229 dBc/Hz Normalized PLL Phase Noise
    • –120.8 dBc/Hz Normalized PLL 1/f Noise
    • 200 MHz Maximum Phase Detector Frequency
    • Programmable Charge Pump Current
  • MULTI-CORE VCO AND OUTPUTS
    • VCO Tuning Range: 1880 – 3760 MHz
    • Programmable Option to Use an External VCO
    • –137 dBc/Hz Phase Noise @ 1 MHz offset for a 2.5 GHz Carrier
    • –155 dBc/Hz Noise Floor
    • Programmable to divide by 1 (bypass), 2, 4, 6, 8, ... , 38
    • Dual Programmable Outputs with Power from –3 to +12 dBm

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Parametrics Compare all products in RF PLLs and Synthesizers

 
Output Frequency (Min) (MHz)
Output Frequency (Max) (MHz)
Normalized PLL Phase Noise (dBc/Hz)
1/f Noise (10 kHz offset at 1 GHz carrier) (dBc/Hz)
Current Consumption (mA)
VCC (V)
Integrated VCO
Rating
Pin/Package
Operating Temperature Range (C)
Approx. Price (US$)
Aux Prescalers
Divider Ratio
LMX2581 LMX2531 LMX2541 TRF3765
50     553     32     300    
3760     3132     4000     4800    
-229     -212     -226     -221    
-125     -104     -125     -106    
135     32     120     190 w/ all 4 buffers on    
3.15 to 3.45     2.8 to 3.2     3.15 to 3.45     3.3    
Yes     Yes     Yes     Yes    
Catalog     Catalog     Catalog     Catalog    
32WQFN     36WQFN     36WQFN     32VQFN    
-40 to 85     -40 to 85     -40 to 85     -40 to 85    
7.00 | 1ku     5.50 | 1ku     6.50 | 1ku     5.65 | 1ku    
    16/17      
1 to 38     1
2    
1 to 127     1
2
4
8    
WEBENCH® Clock Architect - LMX2581
 
Input Frequency
 
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Output Frequency
 
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