Dual, 16-bit, 1.25-GSPS, DAC incorporates a JESD204 serial input to simplify the FPGA interface

June 18, 2012 // By Paul Buckley
Analog Devices, Inc. has introduced a performance-leading 16-bit, 1.25-GSPS transmit D/A converter (DAC) with integrated complex digital modulation functionality, and featuring a JESD204A-compatible serial input.

The AD9128’s high-speed serial interface greatly simplifies and improves the data connection between the DAC and the FPGA in a typical system implementation.

High-performance FPGAs are increasingly being utilized as processors in many data-centric wireless and wired communications, radar, avionics, and medical imaging applications. FPGAs are gaining favor due to their inherent advantages of easier system development, reduced time-to-market, higher processing speed, and on-the-fly programmability. However for higher-resolution, 1-GSPS+ data converter applications, data transfers in and out of an FPGA have traditionally been a design bottleneck because of interface bit-rate limitations, interconnect layout complexity, and parallel interface board space requirements.

JESD204 was specifically developed to remedy these constraints by defining a robust high-speed serial interface that is scalable and accommodates data rates in the multiple Gbps range. ADI is committed to embracing this standard in its ultra-high-speed data-converter technology, and FPGA manufacturers are actively integrating this protocol into their high-performance platforms.

The JESD204A-compliant AD9128 offers high sampling rate and high dynamic range, enabling multicarrier generation up to the Nyquist frequency, and includes features such as an on-chip 32-bit NCO (numerically-controlled oscillator), allowing flexible placement of the IF (intermediate frequency), complex digital modulation, and gain and offset compensation. A 4-wire serial port interface provides for programming and read-back of many of the device’s internal parameters and functions.  The AD9128 supports GSM, WCDMA, TD-SCDMA, CDMA2000, WiMAX, and LTE wireless communications standards.

Availability and Pricing

The AD9128 D/A converter packaged in a 56-lead LFCSP is sampling now and priced at $34.50 each in 1,000 quantities.

More information about the AD9128 D/A converter at