• AD9777 problem

    Hi every one. I want to use AD9777 as a up converter in my design.  am using Spartan 3E as a signal processor and I use DDS core of xilinx to create FM signal and now I have 16 bit value which represent FM signal. data is real and I don`t use I/Q. My question…

  • AD9777 Issue

    Hello,

    I have read the AD9777 Data sheet and i have some quastions regarding the correct use of the device with the evaluation board.

    1)my purpse using the device is to create a 140 MHZ square wave output (IN OUT1) , and my quastion is if i can creat…

  • AD9777: Modulating the bandwidth

    I would like to know if is it possible to use AD9777's Direct-IF option so that
    DAC signal output would be 100-120 MHz (communication signal bandwidth)? This
    would be achieved by upconverting 30-50 MHz band with 70 MHz (Direct-IF?)
  • AD9777 overall delay

    Hi

    I am using the AD9777 in an existing design of a digital feedback controller, so actual input-to-output time delay is critical.

    What is this delay for the AD9777? (the datasheet only gives the settling time, measured from the start of the analog…

  • AD9777 Can I use?

    On the homepage, there is the comment "Not recommend for new design". The customer keeps using this products for long time. Do you have plan to obsolete AD9777? If so, I need to promote other products.

  • AD9777输出频谱问题

    我将35MHz采样率10MHz带宽的复基带信号用35MHz时钟分I、Q两路送进AD9777中,AD9777内设置内插倍数为8倍,Fs/4的IQ调制,complex mix mode,PLL ON,coarse gain adjustment设为最大值,fine gain adjustment设为零,offset adjustment设为零。

    我从FPGA内送35MHz的时钟给AD9777做时钟,然后用AD9777返回的时钟来送基带数据。

    在PCB板上对IoutA和IoutB进行差分转单端,用频谱仪观察输出的频谱如下图所示…

  • AD9777: DATACLK can only be output pin

    I found the below description in the datasheet as is shown in attached file.
    But I can not find any detailed description on the address 02h, Bit 3. I have
    no idea how to set the bit as either input or output. Would you pls give your
  • AD9777输出波形问题

    您好,我最近一直在调一片9777。用FPGA控制9777,并送入数据。

    1.根据手册上寄存器配置表格,我对寄存器配置如下。h

    01h:8'h01;

    02h:8'h20;

    其余寄存器里都是00。

    也就是说,dataclk加强输出,一倍内插,无调制,pll禁用。双端口。

    2.然后我用FPGA对DA进行spi配置,以及10位数据的传输,port1路输入正弦波,port2路全部置1.数据传输速率80MHZ,正弦的数据波形是10MHZ,给DA的工作时钟是80MHZ…

  • AD9777 current increased for a moment

    Hi,

    I used an AD9777 on my board, but recently I found a problem. When I configure the AD9777 via SPI, to turn on the PLL, and use 4x or 8x, the current consumption will incease much more about 300ms, then turn to normal. During configuration, there is…

  • Unused IOUT pins connection of AD9777

    Hi,

    My customer is encountered that should be used only one of the two IOUT pins of AD9777.

    In this case, what is the best solution to connect the unused IOUT pins(IOUTA1/B1 or IOUTA2/B2) ?

    Directly to ground or AC coupled to ground or Not connected…