• How to synchronize two AD9835s?

    This is David from CAST Beijing. I have a quesiton about AD9835.

    How to synchronize two AD9835s? I checked AN-587, but It's for AD9850/1 which have FQ_UD pin.For AD9835, it haven't FQ_UD, then how to synchronize two AD9835s?


  • RE: ad9835 shows 0 volt


    As a first thought, the digital levels of AD9835 and the crystal are not compatible,



    May you replace your crystal for a CMOS compatible? Or decrease your AD9835 supply to 3.3V and escalate appropriately the other digital…

  • Comment on DDS Features Chart

    Corrected mistake.  The AD9835 evaluation board was obsoleted a few years back.  In it's place, the AD9832 evaluation board is recommended, but the AD9832 is limited to a max MCLK of 25MHz whereas the AD9835 can use a max MCLK of 50MHz.

  • RE: AD9835 FSYNC voltage level

    Hi Miguel,


    My AD9835  outputs  0V.

    After power  the AD9835, there is no 1.21V reference if I send a word 0xD000, the refout pin is still  0V reference.

    But, if I  don't power the AD9835, I sent a word 0xD000 directly  then  the 1.21V  reference   can…

  • RE: FSK Data Rate 10Mbps

    Actually found that AD9835 may be useful but I'm not that sure...

  • RE: AD9833 MSK Waveform

    The AD9835 is substantially more power hungry.  It's not an option for my application.

  • AD9835 Documentation

    I am able to successfully program the part, but achieving this stage was problematic because of inconsistencies and contradictions in the documentation which I had to work around. I refer to DATA SHEET ( 41503.pdf ), and APPLICATION NOTE AN-612.

  • AD9835 SPI

    I am planning to user FPGA  GPIO to control data loading, Does it require SPI or Can I directly interface?

  • AD9835 noise


    I'am using an AD9835 to generate a sine wave of 875kHz. The Clock of the DDS is 50MHz. This signal is amplified and travels through a sensor and is rectified and the resulting signal is filtered with a lowpass filter -3dB@10Hz, DC is subtracted and…

  • Using DDS to generate a sine wave consisting of multiple frequencies???

    Good day,

    We looking at using the AD9835 DDS chip.

    We need to generate a sine wave say at 300Hz but also need to superimpose two or more frequencies (say of about 3kHz, 4kHz etc) onto the 300Hz so that the resulting output contains sums and difference…