Wide Band Frac-Integer-N Integrated Synthesizer

The STW81200 is a dual architecture frequency synthesizer (Fractional-N and Integer-N), that features three low phase-noise VCOs with a fundamental frequency range of 3.0 GHz to 6.0 GHz and a programmable dual RF output divider stage which allows coverage from 46.875 MHz to 6 GHz.

The STW81200 optimizes size and cost of the final application thanks to the integration of low- noise LDO voltage regulators and internally-matched broadband RF outputs.

The STW81200 is compatible with a wide range of supply voltages (from 3.0 V to 5.4 V) providing to the end user a very high level of flexibility which trades off excellent performance with power dissipation requirements. A low-power functional mode (software controlled) gives an extra power saving.

Additional features include crystal oscillator core, external VCO mode and output-mute function.

Key Features

  • Output frequency range: 46.875 to 6000 MHz
  • Very Low Noise
    • Normalized in band phase noise floor: -227 dBc/Hz
    • VCO phase noise: -135 dBc/Hz @ 1 MHz offset, 4.0 GHz carrier
    • Noise floor: -160 dBc/Hz
  • Dual architecture frequency synthesizer: Fractional-N and Integer-N
  • Integrated VCOs with automatic center frequency calibration
  • Programmable RF output dividers by 1/2/4/8/16/32/64
  • Dual RF Output broadband matched with programmable power level and mute function
  • External VCO option with 5 V charge pump
  • Integrated low noise LDO voltage regulators
  • Maximum phase detector frequency: 100 MHz
  • Exact frequency mode
  • Fast lock and cycle slip reduction
  • Differential reference clock input (LVDS and LVECPL compliant) supporting up to 800 MHz
  • 13-bit programmable reference frequency divider
  • Programmable charge pump current
  • Digital lock detector
  • Integrated reference crystal oscillator core
  • R/W SPI interface
  • Logic compatibility/tolerance 1.8 V/3.3 V
  • Low Power Functional mode
  • Supply Voltage: 3.0 V to 5.4 V
  • Small size exposed pad VFQFPN36 package 6 x 6 x 1.0 mm
  • Process: BICMOS 0.25 μm SiGe

Circuit Diagram


Technical Documentation

Product Specifications
Description Version Size
DS10185 DS10185: Wideband RF PLL fractional/integer frequency synthesizer with integrated VCOs and LDOs 7.0 3 MB

Tools and Software

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Sample & Buy

Part Number Package Packing Type Marketing Status Unit Price (US$) * Quantity ECCN (EU) ECCN (US) Country of Origin More info Order from ST Order from Distributors
STW81200T VFQFPN 36 6x6x1-0 Tray Active - - NEC EAR99 PHILIPPINES MORE INFO No availability reported, please contact our Sales office
STW81200TR VFQFPN 36 6x6x1-0 Tape And Reel Active - - NEC EAR99 PHILIPPINES MORE INFO No availability reported, please contact our Sales office

(*) Suggested Resale Price per unit (USD) for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office  or our Distributors

Quality & Reliability

Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
STW81200T ActiveVFQFPN 36 6x6x1-0-Ecopack2 0 0
STW81200TR ActiveVFQFPN 36 6x6x1-0-Ecopack2 0 0

(**) The Material Declaration forms available on st.com may be generic documents based on the most commonly used package within a package family. For this reason, they may not be 100% accurate for a specific device. Please contact our sales support for information on specific devices.