LMX2581 Datasheet, PDF (1/30 Pages) Texas Instruments – LMX2581 Wideband Frequency Synthesizer with Integrated VCO

LMX2581
www.ti.com
SNAS601C – AUGUST 2012 – REVISED NOVEMBER 2012
LMX2581 Wideband Frequency Synthesizer with Integrated VCO
Check for Samples: LMX2581
FEATURES
1
2General Features
• 50 – 3760 MHz Operating Frequency
• Low Voltage Logic Compatibility
• Digital Lock Detect
• 32 Pin QFN Package
High Performance PLL
• -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
Broadband Multi-Core VCO
• Tuning Range: 1880 - 3760 MHz
• -137 dBc/Hz Phase Noise @ 1 MHz for a 2.5
GHz Carrier
• Programmable Output Power
• Programmable Option to Use an External VCO
Low Noise VCO Divider
• Programmable to divide by 1 (bypass), 2, 4, 6,
8, ... , 38
• -155 dBc/Hz Noise Floor
TARGET APPLICATIONS
• Wireless Infrastructure (UMTS, LTE, WiMax,
Multi-Standard Base Stations)
• Broadband Wireless
• Wireless Meter Reading
• Test and Measurement
• Clock Generation
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.
The LMX2581 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.
FUNCTIONAL BLOCK DIAGRAM
Low
Noise
LDO
Multiple
Core VCO
Vtune
FLout
Fin
RFoutA
BUFEN
RFoutB
OSCin
MUX
MUX
Output
Divider
Comp
N Divider
MUX
2X
MUX
R
Divider
I
Charge
Pump
CPout
LD
MUXout
Serial Interface
Control
DATA
CLK
LE
CE
1
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2012, Texas Instruments Incorporated