DESCRIPTION

· The Si4133 is a monolithic integrated circuit designed for IF and dual-band RF synthesis in wireless communications. It includes three VCOs, loop filters, reference and VCO dividers, and phase detectors. Divider and powerdown settings are programmable via a three-wire serial interface.

FEATURES

· Dual-band RF synthesizers: RF1 (900 MHz to 1.8 GHz) and RF2 (750 MHz to 1.5 GHz).
· IF synthesizer: 62.5 to 1000 MHz.
· Integrated VCOs, loop filters, varactors, and resonators.
· Requires minimal external components (2).
· Low phase noise.
· Programmable powerdown modes.
· 1 µA standby current.
· 18 mA typical supply current.
· Operates from 2.7 to 3.6 V.
· Available in 24-pin TSSOP and 28-lead MLF packages.

APPLICATIONS

· Dual-band communications.
· Digital cellular telephones: GSM 850, E-GSM 900, DCS 1800, PCS 1900.
· Digital and analog cordless phones.
· Wireless local loop.