Multi-band RF frequency synthesizer with integrated VCOs

The STMicroelectronics STW81103 is an integrated RF synthesizer with voltage controlled oscillators (VCOs). Showing high performance, high integration, low power, and multi-band performances, STW81103 is a low cost one chip alternative to discrete PLL and VCOs solutions.

STW81103 includes an Integer-N frequency synthesizer and two fully integrated VCOs featuring low phase noise performance and a noise floor of -155dBc/Hz. The combination of wide frequency range VCOs (thanks to center frequency calibration over 32 sub-bands) and multiple output options (direct output, divided by 2 or divided by 4) allows to cover the 625MHz-762.5MHz, the 1087.5MHz-1525MHz, the 2175MHz-3050MHz and the 4350MHz-5000MHz bands.

The STW81103 is designed with STMicroelectronics advanced 0.35µm SiGe process.

Key Features

  • Digital lock detector
  • Programmable charge pump current
  • 3.3V power supply
  • Dual digital bus interface: SPI and I2 C bus (fast mode) with 3 bit programmable address (1100A2 A1 A0 )
  • Small size exposed pad VFQFPN28 package 5mm x 5mm x 1.0mm
  • Power down mode (hardware and software)
  • Process: BICMOS 0.35µm SiGe
  • Programmable reference frequency divider (10 bits)
  • 2 programmable counters to achieve a feedback division ratio from 256 to 65551 (prescaler 16/17) and from 361 to 77836 (prescaler 19/20).
  • Integer-N frequency synthesizer
  • Excellent integrated phase noise
  • Dual differential integrated VCOs with automatic center frequency calibration:2500 - 3050 MHz (direct output)4350 - 5000 MHz (direct output)1250 - 1525 MHz (internal divider by 2)2175 - 2500 MHz (internal divider by 2)625 - 762.5 MHz (internal divider by 4)1087.5 - 1250 MHz (internal divider by 4)
  • Dual modulus programmable prescaler (16/17 or 19/20)
  • Phase frequency comparator and charge pump
  • Fast lock time: 150µs

Circuit Diagram

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Technical Documentation

Product Specifications
Description Version Size
DS5385 DS5385: Multi-band RF frequency synthesizer with integrated VCOs 3.2 1 MB
Application Notes
Description Version Size
AN2452 AN2452: STW8110x evaluation board and graphical user interface 3.2 1 MB
AN2491 AN2491: STW8110x hardware component layer API guide 1.2 148 KB
AN2455 AN2455: STWPLLSim phase noise and settling time simulator for STW8110x 2.2 1 MB

Publications and Collaterals

Description Version Size
Integrated multi-band RF synthesizers 1.0 1 MB
Integrated multi-band RF synthesizers 2.1 114 KB

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
STW81103AT VFQFPN2 28 5x5x1.0 Tray Active - - NEC EAR99 PHILIPPINES MORE INFO
STW81103ATR VFQFPN2 28 5x5x1.0 Tape And Reel Active - - NEC EAR99 PHILIPPINES MORE INFO

(*) 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**
STW81103AT ActiveVFQFPN2 28 5x5x1.0IndustrialEcopack1 0 0
STW81103ATR ActiveVFQFPN2 28 5x5x1.0IndustrialEcopack1 0 0

(**) The Material Declaration forms available on 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.