AD9959由四个直接数字频率合成器（DDS）内核构成，每个通道均可提供独立的频率、相位和幅度控制。这种灵活性可用于校正信号之间由滤波、放大等模拟处理或PCB布局失配而引起的不平衡问题。由于所有通道共享一个公共系统时钟，因此它们具有固有的同步性，支持多个设备的同步。
The AD9959 can perform up to 16 orders of frequency, phase, or amplitude modulation (FSK, PSK, ASK). Modulation is performed by applying data to the mode pin. In addition, the AD9959 supports linear frequency, amplitude, or phase scanning, making it suitable for radar, instrumentation, and other applications.
The AD9959's serial I/O ports support a wide range of configurations, providing great flexibility. Similar to the SPI operating mode provided in Analog Devices' previous DDS products, the serial I/O ports provide SPI-compatible operating mode. Four data pins (SDIO_0/SDIO_1/SDIO_2/SDIO_3) correspond to four programmable modes for serial I/O, providing flexibility.
The AD9959 features advanced DDS technology to deliver high performance at low power consumption. The device integrates four high-speed 10-bit DACs with superior wideband and narrowband SFDR performance. Each channel has a dedicated 32-bit frequency tuning word, 14-bit phase offset, and a 10-bit output scale multiplier.
The DAC output is based on the supply voltage as a reference source and must be connected to the AVDD via a resistor or AVDD center tap transformer. Each DAC has its own programmable reference source for achieving a different full-scale current for each channel.
This DDS can be used as a high-resolution crossover when REFCLK is used as input and output is provided by the DAC. All channels share a REFCLK input source, which can be driven directly or used with a built-in REFCLK Multiplier (PLL) up to 500 MSPS. The PLL multiplier factor is programmable in the range of 4~20, and the step is an integer. The REFCLK input also has an oscillation circuit that allows an external crystal oscillator to be used as a REFCLK source. The frequency of the crystal oscillator must be between 20 MHz and 30 MHz. The crystal oscillator can be used with the REFCLK multiplier.
The AD9959 is available in a space-saving 56-pin LFCSP package. The DDS cores (AVDD and DVD pins) are powered from a 1.8 V supply. The digital I/O interface (SPI) operates at 3.3 V and requires the connection of DVDD_I/O (pin 49) to 3.3 V.
The AD9959 can operate in an industrial temperature range of -40°C~+85°C.
apply
捷变本振（LO）频率合成
相控阵雷达/声纳
仪器仪表
同步时钟
用于AOTF（声光可调滤波器）的RF源