Description
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 lownoise LDO voltage regulators and internallymatched 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. VFQFPN36

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

Applications
■ Cellular/4G infrastructure equipment
■ Instrumentation and test equipment
■ Cable TV
■ Other wireless communication systems