The AD9776/AD9778/AD9779 are dual, 12-/14-/16-bit, high dynamic range, digital-to-analog converters (DACs) that provide a sample rate of 1 GSPS, permitting multicarrier generation up to the Nyquist frequency. They include features optimized for direct conversion transmit applications, including complex digital modulation, and gain and offset compensation. The DAC outputs are optimized to interface seamlessly with analog quad-rature modulators such as the AD8349. A serial peripheral interface (SPI®) provides for programming/readback of many internal parameters. Full-scale output current can be programmed over a range of 10 mA to 30 mA. The devices are manufactured on an advanced 0.18 microm CMOS process and operate on 1.8 V and 3.3 V supplies for a total power consumption of 1.0 W. They are enclosed in 100-lead TQFP packages.
- Low power: 1.0 W at 1 GSPS, 600 mW at 500 MSPS, full operating conditions
- SFDR = 78 dBc to fOUT = 100 MHz
- Single carrier WCDMA ACLR = 79 dBc @ 80 MHz IF
- Analog output: adjustable 8.7 mA to 31.7 mA, RL = 25 to 50 ohms
- Novel 2x, 4x, and 8x interpolator/coarse complex modulator allows carrier placement anywhere in DAC bandwidth
- Auxiliary DACs allow control of external VGA and offset control
- Multiple chip synchronization interface
- High performance, low noise PLL clock multiplier
- Digital inverse sinc filter
- 100-lead, exposed paddle TQFP package
