GENERAL DESCRIPTION

The AD9122 is a dual 16-bit, high dynamic range, digital-to analog converter (DAC) that provides a sample rate of 1200 MSPS, permitting a multicarrier generation up to the Nyquist frequency. It includes 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 quadrature modulators, such as the ADL537x F-MOD series from Analog Devices, Inc. A 4-wire serial port interface provides for programming/readback of many internal parameters. Full-scale output current can be programmed over a range of 8.7 mA to 31.7 mA. The AD9122 comes in a 72-lead LFCSP.

FEATURES

Flexible LVDS interface allows word, byte, or nibble load

Single-carrier W-CDMA ACLR = 82 dBc @ 122.88 MHz IF

Analog output: adjustable 8.7 mA to 31.7 mA, RL = 25 Ω to 50 Ω

Novel 2×/4×/8× interpolator/complex modulator allows carrier placement anywhere in the DAC bandwidth

Digital gain and phase adjustment for sideband suppression

Multiple chip synchronization interfaces

High performance, low noise PLL clock multiplier

Digital inverse sinc filter

Flexible LVDS interface allows word, byte, or nibble load

Low power: 1.5 W @ 1.2 GSPS, 800 mW @ 500 MSPS, full operating conditions

72-lead, exposed paddle LFCSP