LT5558 Series

600MHz to 1100MHz High Linearity Direct Quadrature Modulator

Catalog

600MHz to 1100MHz High Linearity Direct Quadrature Modulator

Part	Function	LO Frequency [Max]	LO Frequency [Min]	Current - Supply	Noise Floor	Mounting Type	Supplier Device Package	RF Frequency [Max]	RF Frequency [Min]	Test Frequency	P1dB	Package / Case	Output Power	Voltage - Supply [Min]	Voltage - Supply [Max]
Analog Devices LT5558EUF#PBF	Modulator	1.1 GHz	600 MHz	108 mA	-158 dBm/Hz	Surface Mount	16-QFN (4x4)	1.1 GHz	600 MHz	900 MHz	7.8 dBm	16-WQFN Exposed Pad	-1.1 dBm	4.5 V	5.25 V

Catalog

600MHz to 1100MHz High Linearity Direct Quadrature Modulator

Key Features

• Direct Conversion from Baseband to RF

• High OIP3: + 22.4dBm at 900MHz

• Low Output Noise Floor at 20MHz Offset:No RF: –158dBm/HzPOUT= 4dBm: –152.7dBm/Hz

• No RF: –158dBm/Hz

• POUT= 4dBm: –152.7dBm/Hz

• Low Carrier Leakage: –43.7dBm at 900MHz

• High Image Rejection: –49dBc at 900MHz

• 3 Channel CDMA2000 ACPR: –70.4dBc at 900MHz

• Integrated LO Buffer and LO Quadrature Phase Generator

• 50Ω AC-Coupled Single-ended LO and RF Ports

• High Impedance Interface to Baseband Inputs with 2.1V Common Mode Voltage

• 16-Lead QFN 4mm × 4mm Package

Description

The LT5558 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 GSM, EDGE, CDMA, CDMA2000, and other systems. It may also be conﬁ gured 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 doublebalanced 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 single-ended output. The balanced I and Q baseband input ports are intended for DC coupling from a source with a common-mode voltage level of about 2.1V. The LO path consists of an LO buffer with single-ended input, and precision quadrature generators which produce the LO drive for the mixers. The supply voltage range is 4.5V to 5.25V.ApplicationsRFID Single-Sideband TransmittersInfrastructure TX for Cellular and ISM BandsImage Reject Up-Converters for Cellular BandsLow-Noise Variable Phase-Shifter for 600MHz to 1100MHz Local Oscillator SignalsMicrowave Links