Quad 16-Bit,1GSPS DAC TxDAC+ Digital-to-Analog Converter

The AD9148 is a quad, 16-bit, high dynamic range, digital-to-analog converter (DAC) that provides a sample rate of 1000 MSPS. These devices include features optimized for direct conversion transmit applications, including gain, phase, and offset compensation. The DAC outputs are optimized to interface seamlessly with analog quadrature modulators such as the ADL5371 / ADL5372 / ADL5373 / ADL5374 /ADL5375. A serial peripheral interface (SPI) is provided for programming of the internal device parameters. Full-scale output current can be programmed over a range of 10 mA to 30 mA. The devices operate from 1.8 V and 3.3 V supplies for a total power consumption of 3 W at the maximum sample rate. They are enclosed in 196-ball chip scale package ball grid array with the option of an attached heat spreader.

PRODUCT HIGHLIGHTS

* Low noise and intermodulation distortion (IMD) enable high quality synthesis of wideband signals from baseband to high intermediate frequencies.

* A proprietary DAC output switching technique enhances dynamic performance.

* The current outputs are easily configured for various single-ended or differential circuit topologies.

* The LVDS data input interface includes FIFO to ease input timing.

APPLICATIONS

* Wireless infrastructure

* LTE, TD-SCDMA, WiMAX, W-CDMA, CDMA2000, GSM

* MIMO/transmit diversity

* Digital high or low IF synthesis

* Single carrier WCDMA ACLR = 80 dBc @ 150 MHz IF

* Channel to Channel Isolation > 90dB

* Analog output

* Adjustable 8.7 mA to 31.7 mA

* RL = 25 Ω to 50 Ω

* Novel 2×, 4× and 8x interpolator eases data interface

* On-chip fine complex NCO allows carrier placement anywhere in DAC bandwidth