Single-Chip Synthesizer Backs Wireless Basestations

The AD9858 integrated synthesizer combines a 1-Gsample/s direct digital synthesizer (DDS) and a 10-bit digital-to-analog converter (DAC) on one chip. Equipped with fast-frequency-hopping and fine-tuning resolution functionalities, it will make its way into wireless infrastructure as well as military and aerospace radar applications. On-chip functional blocks include a 2-GHz RF mixer, a 150-MHz phase detector, and a programmable charge pump with proprietary fast-locking acquisition logic. The chip also features a 32-bit phase accumulator and 14-bit phase-offset adjustment. The DDS can directly generate frequencies up to 400 MHz when driven at a 1-GHz internal clock speed. Using the on-chip divide-by-two feature, the reference clock can be derived from an external clock source of up to 2 GHz. To reduce power consumption, the synthesizer incorporates a programmable full-sleep mode. Packaged in a 100-lead EPAD-TQFP, the AD9858 costs $49.50 in 1000-unit quantities.

Analog Devices Inc.
www.analog.com; (800) ANALOG-D