Broadband Quadrature Modulator Targets Cable, Satellite, And Wireless Infrastructure Applications

Norwood, MA -- Analog Devices is expanding its portfolio of radio frequency integrated circuits with a quadrature modulator that operates from 50 MHz to 2200 MHz, making it well-suited for low intermediate frequency (IF) and RF applications such as broadband wireless access systems, microwave radio link transmitters, cable modem termination systems and cellular infrastructure. Requiring only a single-ended, two-times local oscillator (LO) input, the ADL5385 converts complex modulation information from the baseband to the final RF input, over a broad range of LO frequencies.

The ADL5385 provides high output power capability (+10 dBm P1dB), high single-ended output linearity (+24 dBm IP3), and low noise floor (–158 dBm/Hz). The –46 dBm carrier feedthrough and –50 dBc sideband suppression at 140 MHz minimizes the need for calibration and nulling in complex high-order modulation applications such as 16 QAM and greater.

The ADL5385 accepts wideband inputs from dc to 700 MHz that are compatible with the output levels of ADI's AD977x family of TxDAC+ transmit digital-to-analog converters (DACs). The ADL5385 low LO drive requirement of –7 dBm is also compatible with ADI's ADL4360 series of integrated phase locked loop (PLL) with VCO products. The 2× LO input frequency of the ADL5385 helps to minimize LO pulling in applications where LO isolation and board density are critical.

The ADL5385 is sampling now, with full-production quantities available in September 2006.

SOURCE: Analog Devices, Inc.