DDS Line Offers High-Speed Operation

The AD9852 and AD9854 monolithic ICs directly synthesize dc to 120-MHz analog sinewaves. This device is said to represent a significant performance improvement compared with similar direct digital synthesis (DDS) solutions that are large, expensive, power-hungry hybrids. The AD9852 contains a built-in 12-bit/300-MHz digital-to-analog converter (DAC), while the AD9854 offers dual, on-chip 12-bit DACs for precise quadrature outputs. Both devices offer a 48-bit tuning word that yields a tuning resolution of 1.066 MHz. The small size and integrated functionality of these digital synthesizers include a programmable 4x to 20x reference clock multiplier, chirp (automatic frequency sweeping), and output amplitude ramping. Applications are high-speed clock generators for communications, digital tuning, local oscillator synthesizers, pixel clock generators, and FSK modulators.