• AD9257 AGND circuit

    There are three GND below in our system.



    GND for the image sensor

    (image sensor is CMOS with analog output)

    Connection of GND is shown below.

    Image sensor GND---AGND---DGND

    ADC will receive the signal from the sensor.

    Does GND of AD9257…

  • AD9257: Digital Reset


    I have a question about the digital reset of AD9257.

    The digital reset is the following sequence.

    SPI_Write(0x08, 0x03);

    SPI_Write(0x08, 0x00);

    How long waiting time is necessary from writing 0x03 to writing 0x00?

    Is waiting time of about…

  • AD9257: Initialization time


    I have a question about the AD9257.

    I turn on the power supply of ADC in the state to which the clock is steady.

    And, the first analog to digital conversion data becomes valid.

    I want to know the time until valid conversion data is output after…

  • AD9257 SPI issue


    I have troubles with SPI communication between AD9257 demo board and a zybo board.

    For example, I try to read the register 0x01(the chip ID) with this command, but as you can see the ADC doesn't answer...

    We check timing spec, and it is OK.


  • Questions about AD9257

    Hello support team,

    Please advice me about below questions related to AD9257.

    1. I advised that Digital-reset(as shown below) after powerup in order to initialize a core of ADC.
       SPI_Write(0x08,0x03);#Digital Reset
       SPI_Write(0x08,0x00);#Normal Opera…

  • AD9252/AD9257 sample program

    We have some issues about the Sampling time sequence of AD9252/9257, the output is nothing, so we hope you can provide the sample program to me to help to revise our program.

  • document of AD9257-65EBZ

    Dear Sir/Madam,

    We are going to evaluate the AD9257 using AD9257-65EBZ and HSC-ADC-EVALCZ.

    Do you have a document of AD9257-65EBZ?.

    We have checked on web-site,but could not found that.


  • RE: AD9257 reset control

    Hello Tak-san,

    Thank you for your questions.

    1. Yes, you are correct. When a digital reset (Register 0x08 = 0x03 --> 0x00) is invoked, the AD9257 goes into an initialization phase where an internal state machine sets up the biases and the registers…

  • Resolution change of AD9257

    Dear Sir/Madam,

    I have the question for your AD9257 "Resolution/ Sample rate override" from our customer.

    After send the register setting for "Resolution/ sample rate override", customer make change "transfer register" bit0;0 to 1, so "Resolution…

  • Questions about AD9257

    1) The data sheet is shown the effect of jitter of the input clock. (Page 22)

        Does this mean the effects of jitter of the rising edge?

    2) Jitter of the falling edge of the input clock signal will affect the performance of the ADC?

       If it is correct…