Dual DAC Races At 1 Gsamples/s

Emerging as the fastest 16-bit, dual d/a converter, the AD9779 achieves a sample rate of 1 Gsamples/s, reportedly twice as fast as comparable devices while consuming up to 36% less power. The device operates from a single supply, 1.8V digital and 3.3V analog, and consumes 600 mW at 500 Msamples/s and 1W at 1 Gsamples/s. Features include digital interpolation filters, a complex digital modulator, and a digital mixer. These features promise to simplify the digital interface and allow some digital signal processing functions to be moved out of the FPGA or ASIC. Another reported benefit of on-chip filtering is relaxation of the analog reconstruction filters, which eases performance requirements to reduce board space and total system cost while improving manufacturability. Additional features include an ACLR of 87 dBc at an IF of 80 MHz, a CMOS data interface with auto-tracking input timing, and an adjustable analog output from 10 mA to 30 mA into loads from 25Ω to 50Ω. Sampling now in a 100-lead, exposed-paddle TQFP with production in May, price is $27.95 each/1,000. ANALOG DEVICES INC., Wilmington, MA. (800) 262-5643.