NOISE FLOOR AT 30MHz OFFSET (dBm/Hz) LT5568 700MHz 1050MHz High Linearity Direct Quadrature Modulator FEATURES DESCRIPTIO Frequency Range: 700MHz to 1050MHz The LT 5568 is a direct I/Q modulator designed for high High OIP3: +22.9dBm at 850MHz performance wireless applications, including wireless Low Output Noise Floor at 5MHz Offset: infrastructure. It allows direct modulation of an RF signal No RF: 160.3dBm/Hz using differential baseband I and Q signals. It supports P = 4dBm: 154dBm/Hz PHS, GSM, EDGE, TD-SCDMA, CDMA, CDMA2000, W- OUT 3-Ch CDMA2000 ACPR: 71.4dBc at 850MHz CDMA, and other systems. It may also be con gured Integrated LO Buffer and LO Quadrature Phase as an image reject upconverting mixer, by applying Generator 90 phase-shifted signals to the I and Q inputs. The I/Q 50 AC-Coupled Single-Ended LO and RF Ports baseband inputs consist of voltage-to-current converters 50 DC Interface to Baseband Inputs that in turn drive double-balanced mixers. The outputs of Low Carrier Leakage: 43dBm at 850MHz these mixers are summed and applied to an on-chip RF High Image Rejection: 46dBc at 850MHz transformer, which converts the differential mixer signals 16-Lead 4mm 4mm QFN Package to a 50 single-ended output. The four balanced I and Q baseband input ports are intended for DC coupling from a U source with a common mode voltage level of about 0.5V. APPLICATIO S The LO path consists of an LO buffer with single-ended Infrastructure Tx for Cellular Bands input, and precision quadrature generators that produce Image Reject Up-Converters for Cellular Bands the LO drive for the mixers. The supply voltage range is Low-Noise Variable Phase-Shifter for 700MHz to 4.5V to 5.25V. 1050MHz Local Oscillator Signals , LTC and LT are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. RFID Reader TYPICAL APPLICATIO CDMA2000 ACPR, AltCPR and Noise vs RF 700MHz to 1050MHz Direct Conversion Transmitter Application Output Power at 850MHz for 1 and 3 Carriers 50 125 5V DOWNLINK TEST MODEL 64 DPCH V CC 1-CH. 100nF ACPR LT5568 x2 RF = 700MHz TO 1050MHz I-DAC V-I 60 135 3-CH. ACPR I-CHANNEL PA 0 EN 70 145 90 3-CH. AltCPR BALUN Q-CHANNEL Q-DAC V-I 1-CH. AltCPR 80 155 3-CH. NOISE 1-CH. NOISE 5568 TA01 BASEBAND 90 165 GENERATOR VCO/SYNTHESIZER 30 25 20 15 10 5 RF OUTPUT POWER PER CARRIER (dBm) 5568 TA02 5568f 1 ACPR, AltCPR (dBc) U ULT5568 UUW ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Note 1) TOP VIEW Supply Voltage .........................................................5.5V Common Mode Level of BBPI, BBMI and 16 15 14 13 BBPQ, BBMQ .......................................................2.5V EN 1 12 GND Operating Ambient Temperature GND 2 11 RF 17 (Note 2) ............................................... 40C to 85C LO 3 10 GND Storage Temperature Range ................... 65C to 125C GND 4 9 GND 5 6 7 8 Voltage on any Pin Not to Exceed ...................... 500mV to V + 500mV CC UF PACKAGE 16-LEAD (4mm 4mm) PLASTIC QFN T = 125C, = 37C/W JMAX JA EXPOSED PAD (PIN 17) IS GROUND, MUST BE SOLDERED TO PCB ORDER PART NUMBER UF PART MARKING LT5568EUF 5568 Order Options Tape and Reel: Add TR Lead Free: Add PBF Lead Free Tape and Reel: Add TRPBF Lead Free Part Marking: