Home RF & microwave RF PLLs & synthesizers
Home
RF & microwave
RF PLLs & synthesizers

LMX2581

ACTIVE

3.76-GHz wideband frequency synthesizer with integrated VCO

Order now
Data sheet

LMX2581

ACTIVE
Data sheet Order now

Product details

Frequency (max) (MHz) 3760 Frequency (min) (MHz) 50 Normalized PLL phase noise (dBc/Hz) -229 1/f noise (10-kHz offset at 1-GHz carrier) (dBc/Hz) -125 Features Integrated VCO, Wideband Current consumption (mA) 178 Integrated VCO Yes Operating temperature range (°C) -40 to 85 Rating Catalog Lock time (µs) (typ) (s) 10
Frequency (max) (MHz) 3760 Frequency (min) (MHz) 50 Normalized PLL phase noise (dBc/Hz) -229 1/f noise (10-kHz offset at 1-GHz carrier) (dBc/Hz) -125 Features Integrated VCO, Wideband Current consumption (mA) 178 Integrated VCO Yes Operating temperature range (°C) -40 to 85 Rating Catalog Lock time (µs) (typ) (s) 10
WQFN (RTV) 32 25 mm² 5 x 5
  • Output Frequency from 50 to 3760 MHz
  • Input Clock Frequency up to 900 MHz
  • Phase Detector Frequency up to 200 MHz
  • Supports Fractional and Integer Modes
  • –229 dBc/Hz Normalized PLL Phase Noise
  • –120.8 dBc/Hz Normalized PLL 1/f Noise
  • –137 dBc/Hz VCO Phase Noise @ 1 MHz
    offset for a 2.5 GHz Carrier
  • 100 fs RMS Jitter in Integer Mode
  • Programmable Fractional Modulator Order
  • Programmable Fractional Denominator
  • Programmable Output Power up to +12 dBm
  • Programmable 32 Level Charge Pump Current
  • Programmable Option to Use an External VCO
  • Digital Lock Detect
  • 3-Wire Serial Interface and Readback
  • Single Supply Voltage from 3.15 V to 3.45 V
  • Supports Logic Levels down to 1.6 V
  • Output Frequency from 50 to 3760 MHz
  • Input Clock Frequency up to 900 MHz
  • Phase Detector Frequency up to 200 MHz
  • Supports Fractional and Integer Modes
  • –229 dBc/Hz Normalized PLL Phase Noise
  • –120.8 dBc/Hz Normalized PLL 1/f Noise
  • –137 dBc/Hz VCO Phase Noise @ 1 MHz
    offset for a 2.5 GHz Carrier
  • 100 fs RMS Jitter in Integer Mode
  • Programmable Fractional Modulator Order
  • Programmable Fractional Denominator
  • Programmable Output Power up to +12 dBm
  • Programmable 32 Level Charge Pump Current
  • Programmable Option to Use an External VCO
  • Digital Lock Detect
  • 3-Wire Serial Interface and Readback
  • Single Supply Voltage from 3.15 V to 3.45 V
  • Supports Logic Levels down to 1.6 V

The LMX2581 is a low noise wideband frequency synthesizer that integrates a delta-sigma fractional N PLL, multiple core VCO, programmable output divider, and two differential output buffers. The VCO frequency range is from 1880 to 3760 MHz and can be sent directly to the output buffers or divided down by even values from 2 to 38. Each buffer is capable of output power from –3 to +12 dBm at 2700 MHz. Integrated low noise LDOs are used for superior noise immunity and consistent performance.

This synthesizer is a highly programmable device and it enables the user to optimize its performance. In fractional mode, the denominator and the modulator order are programmable and can be configured with dithering as well. The user also has the ability to directly specify a VCO core or entirely bypass the internal VCO. Finally, many convenient features are included such as power down, Fastlock, auto mute, and lock detection. All registers can be programmed through a simple 3 wire interface and a read back feature is also available.

The LMX2581 operates on a single 3.3 V supply and comes in a 32 pin 5.0 mm × 5.0 mm WQFN package.

The LMX2581 is a low noise wideband frequency synthesizer that integrates a delta-sigma fractional N PLL, multiple core VCO, programmable output divider, and two differential output buffers. The VCO frequency range is from 1880 to 3760 MHz and can be sent directly to the output buffers or divided down by even values from 2 to 38. Each buffer is capable of output power from –3 to +12 dBm at 2700 MHz. Integrated low noise LDOs are used for superior noise immunity and consistent performance.

This synthesizer is a highly programmable device and it enables the user to optimize its performance. In fractional mode, the denominator and the modulator order are programmable and can be configured with dithering as well. The user also has the ability to directly specify a VCO core or entirely bypass the internal VCO. Finally, many convenient features are included such as power down, Fastlock, auto mute, and lock detection. All registers can be programmed through a simple 3 wire interface and a read back feature is also available.

The LMX2581 operates on a single 3.3 V supply and comes in a 32 pin 5.0 mm × 5.0 mm WQFN package.
filter Find other RF PLLs & synthesizers
Download View video with transcript Video

Similar products you might be interested in

open-in-new Compare alternates
Similar functionality to the compared device
LMX2531 ACTIVE High performance frequency synthesizer system with integrated VCO Very Low Power RF Synthesizer
LMX2541 ACTIVE Ultra-low noise PLLatinum frequency synthesizer with integrated VCO RF Synthesizer With Extremely Low Spurs

Technical documentation

star =Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 1
Top documentation Type Title Format options Date
* Data sheet LMX2581 Wideband Frequency Synthesizer with Integrated VCO datasheet (Rev. G) PDF | HTML 05 Sep 2014

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Evaluation board

LMX2581EVM — LMX2581 evaluation module

The LMX2581 Wideband frequency synthesizer allows the generation of a broad range of frequencies with excellent phase noise. The LMX2581 Reference Board (LMX2581EVM) is designed to assist in the evaluation of the LMX2581 in a system, as well as serve as a reference design for the customer’s (...)

User guide: PDF
Not available on TI.com
Software programming tool

CODELOADER — CodeLoader Device Register Programming v4.19.0

The CodeLoader 4 software is used to program the LMX PLLs and LMK timing devices through either the USB or line print terminal (LPT) port of a computer. This software also provides information on how to program the device by showing the bits that are actually sent.

Which software do I use?

Product

(...)

Supported products & hardware

Supported products & hardware
Download
Support software

CLOCKDESIGNTOOL — Clock Design Tool Software

The Clock Design Tool software helps with part selection, loop filter design and simulation of timing device solutions. When you enter desired output frequencies and a reference frequency (optional), the tool provides TI devices to meet the specified requirements, divider values and a recommended (...)

Supported products & hardware

Supported products & hardware
Download
Support software

TICSPRO-SW — TICS Pro GUI and Live Programming Tool for Clocking Devices

Texas Instruments clocks and synthesizers (TICS) pro software is used to program the evaluation modules (EVMs) for product numbers with these prefixes: CDC, LMK and LMX. These products include phase-locked loops and voltage-controlled oscillators (PLL+VCO), synthesizers and clocking devices.

Supported products & hardware

Supported products & hardware
Download options
Simulation model

LMX2581 IBIS Model

SNAM157.ZIP (54 KB) - IBIS Model
Download
Design tool

CLOCK-TREE-ARCHITECT — Clock tree architect programming software

Clock tree architect is a clock tree synthesis tool that streamlines your design process by generating clock tree solutions based on your system requirements. The tool pulls data from an extensive database of clocking products to generate a system-level multi-chip clocking solution.
Design now
Design tool

PLLATINUMSIM-SW — PLL loop filter, phase noise, lock time, and spur simulation tool

PLLATINUMSIM-SW is a simulation tool that allows users to create detailed designs and simulations of our PLLatinum™ integrated circuits, which include the LMX series of phase-locked loops (PLLs) and synthesizers.

Supported products & hardware

Supported products & hardware
Download options
Reference designs

TIDA-00360 — 700–2700 MHz Dual-Channel Receiver with 16-Bit ADC and 100 MHz IF Bandwidth Reference Design

The increasing demand on wireless networks to provide faster data links to customers has driven transceiver hardware to increasingly demanding performance with enough bandwidth to support the largest standardized multi-carrier frequency bands (with band aggregation in some cases) and enough (...)
Design guide: PDF
Schematic: PDF
Reference designs

TIDA-00426 — 12-Gbps Multi-Channel BERT Board Reference Design

This reference design is a 12-Gbps low-cost bit error tester (BERT) capable of generating and checking up to 8 channels of pseudo-random binary sequences (PRBS). This validated design is a convenient way to generate multi-channels high speed serial bit streams of up to 12-Gbps, and checking (...)
Design guide: PDF
Schematic: PDF
Package Pins CAD symbols, footprints & 3D models
WQFN (RTV) 32 Ultra Librarian
TI's Standard Terms and Conditions for Evaluation Items apply.

Ordering & quality

Information included:
  • RoHS
  • REACH
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring
Information included:
  • Fab location
  • Assembly location

Recommended products may have parameters, evaluation modules or reference designs related to this TI product.

Support & training

TI E2E™ forums with technical support from TI engineers

View all forum topics

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​​​​​​​

Videos