Maxim Integrated Products has announced the MAX5879 multi-Nyquist RF digital-to-analog converter (RF DAC) to deliver a fully digital software-defined radio (SDR) transmitter. This solution enables a common hardware platform for multicarrier, multiband, and multistandard base stations.
The MAX5879 RF DAC architecture, working with FPGA-based direct digital synthesis (DDS), shifts the functions of the analog quadrature modulator and agile local oscillator (LO) used in current architectures into the digital domain. This eliminates in-phase and quadrature errors, and LO feedthrough, commonly associated with analog upconversion. The MAX5879 simplifies RF design and improves reliability for base-station transmitters.
The MAX5879's selectable frequency response modes support direct RF synthesis of common 3G/4G cellular bands in multiple Nyquist zones from 700MHz to 2.8GHz. A single MAX5879 RF DAC serves multiple standards such as multicarrier GSM, WCDMA and LTE that allows designers to use a common hardware platform that cuts development time-to-market.
Benefits of an MAX5879-enabled digital transmitter:
1. The RF DAC-enabled transmitter delivers wider bandwidths than traditional architectures for smartphones and tablet computers.
2. The selectable 4:1 and 2:1 input data multiplexer reduces input word rates.
3. The RF-DAC technology is suitable for microwave radio links used in mobile backhaul equipment; for CMTS/edge-QAM boxes used in cable head-end equipment; and for other wideband communication systems.
The device has an operating temperature range of -40°C to +85°C and is packaged in 256-ball (17 x 17 mm) CSBGA. The DAC is fully released and is in production.
Data sheet: http://www.maxim-ic.com/MAX5879