LT5571 Datasheet | Linear Technology

.. Features - - - - LT5571 620MHz - 1100MHz High Linearity Direct Quadrature Modulator DESCRIPTION The LT®5571 is a direct I/Q modulator designed for high performance wireless applications, including wireless infrastructure. It allows direct modulation of an RF signal using differential baseband I and Q signals. It supports RFID, GSM, EDGE, CDMA, CDMA2000, and other systems. It may also be configured as an image reject upconverting mixer by applying 90° phase-shifted signals to the I and Q inputs. The high impedance I/Q baseband inputs consist of voltage-to-current converters that in turn drive double-balanced mixers. The outputs of these mixers are summed and applied to an on-chip RF transformer, which converts the differential mixer signals to a 50Ω singleended output. The four balanced I and Q baseband input ports are intended for DC-coupling from a source with a mon-mode voltage at about 0.5V. The LO path consists of an LO buffer with single-ended input, and precision quadrature generators that produce the LO drive for the mixers. The supply voltage range is 4.5V to 5.25V. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. - - - - - - - Direct Conversion from Baseband to RF High Output: - 4.2d B Conversion Gain High OIP3: 21.7d Bm at 900MHz Low Output Noise Floor at 20MHz Offset: No RF: - 159d Bm/Hz POUT = 4d Bm: - 153.3d Bm/Hz Low Carrier Leakage: - 42d Bm at 900MHz High Image Rejection: - 53d Bc at 900MHz 3-Ch CDMA2000 ACPR: - 70.4d Bc at 900MHz Integrated LO Buffer and LO Quadrature Phase Generator 50Ω AC-Coupled Single-Ended LO and RF Ports High Impedance DC Interface to Baseband Inputs with 0.5V mon Mode Voltage 16-Lead QFN 4mm × 4mm Package APPLICATIONS - - - - - RFID Interrogators GSM, CDMA, CDMA2000 Transmitters Point-to-Point Wireless Infrastructure Tx Image Reject Up-Converters for Cellular Bands Low-Noise Variable Phase-Shifter for 620MHz to...