Weybridge, UK — Analog Devices claims an industry first by integrating automatic gain control (AGC) circuitry into its high-performance broadband I/Q quadrature modulator, all within a compact 6-mm x 6-mm LFCSP (lead-frame chip-scale package). The ADL5386 provides a unique combination of performance and integration for low IF (intermediate frequency) and RF (radio frequency) transmitters within broadband wireless access systems, microwave radio links, cable modem termination systems and cellular infrastructure equipment.
Operating over a 50-MHz to 2200-MHz frequency range, the ADL5386 supports high-data-rate complex modulation for next-generation communication infrastructure equipment. Functionally complete, the modulator integrates a 25-dB dynamic range output power detector and a VVA (voltage variable attenuator). Together, they form a closed-loop automatic level control (ALC) or AGC, enabling the modulator to accurately set the output power to a user determined level.
The device provides a complete subsystem within a small footprint, saving considerable board space, component cost, and circuit complexity over discrete implementations.
The broadband I/Q quadrature modulator provides exceptional output dynamic range due to its high output power capability (+10 dBm P1dB), high single-ended output linearity (+24 dBm IP3), and low noise floor (-160 dBm/Hz). The -38 dBm carrier feedthrough and -46 dBc sideband suppression at 350 MHz minimizes the need for calibration and nulling in complex high-order modulation applications such as 64 QAM (quadrature amplitude modulation) and greater.
The ADL5386 wideband inputs (DC to 700 MHz) are compatible with the output levels of the company's AD977x family of TxDAC+® (transmit digital-to-analog converter) devices. The -7 dBm local oscillator (LO) drive requirement is compatible with the company's ADF4360 series of integrated PLL (phase locked loop) synthesizers. The 2 x LO input frequency of the ADL5386 helps to minimize LO pulling in applications where LO isolation and board density are critical.
Further information and a data sheet for the ADL5386 are available.