Analog Devices' AD9119 and AD9129 are high performance, 11-/14-bit RF digital-to-analog converters (DACs) supporting data rates up to 2.8 GSPS. The DAC core is based on a quad-switch architecture that enables dual-edge clocking operation, effectively increasing the DAC update rate to 5.6 GSPS when configured for Mix-Mode™ or 2× interpolation. The high dynamic range and bandwidth enable multicarrier generation up to 4.2 GHz.
In baseband mode, wide bandwidth capability combines with high dynamic range to support from 1 to 158 contiguous carriers for CATV infrastructure applications. A choice of two optional 2× interpolation filters is available to simplify the post-reconstruction filter by effectively increasing the DAC update rate by a factor of 2. In Mix-Mode operation, the AD9119 and AD9129 can reconstruct RF carriers in the second and third Nyquist zone while still maintaining exceptional dynamic range up to 4.2 GHz. The high performance NMOS DAC core features a quad-switch architecture that enables industry-leading direct RF synthesis performance with minimal loss in output power. The output current can be programmed over a range of 9.5 mA to 34.4 mA.
The AD9119 and AD9129 each include several features that may further simplify system integration. A dual-port, source synchronous LVDS interface simplifies the data interface to a host FPGA/ASIC. A differential frame/parity bit is also included to monitor the integrity of the interface. On-chip delay locked loops (DLLs) are used to optimize timing between different clock domains.
- Direct RF synthesis at 2.8 GSPS data rate
- DC-to-1.4 GHz in baseband mode
- DC-to-1.0 GHz in 2x interpolation mode
- 1.4 to 4.2 GHz in mix-mode
- DAC update rate of up to 5.6 GSPS
- Bypassable 2x interpolation
- Excellent dynamic performance
- DOCSIS 3.0 wideband ACLR/Harmonic performance
- 8 QAM carriers: ACLR > 65 dBc