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AD9102 SPI clock polarity

Thread Summary

The user inquired about the active edge of the SPI clock for the AD9102 waveform generator. The final answer confirmed that the AD9102 captures SPI data on the rising edge of SCLK. The user also noted issues with the built-in pseudorandom noise generator, which only jumps between two discrete values, and was informed that the PN generator waveform is fixed and can only be selected using the PRESTORE_SEL bit field.
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Hello,

I'm designing a waveform generator with the new AD9102 device, and discovered that the data sheet does not clearly specify which edge of the SPI clock is active.  There is a qualitative timing diagram in the "SPI PORT" section of the data sheet that seems to show that when writing to the device, data is transferred on the rising edge of the clock.  Is this correct?  If so, it is opposite from the convention for many Analog Devices DACs (including the excellent new AD5689R, for which I completed and tested a little circuit card just this morning).  However, it appears that a lot of DDS chips use the rising edge of the clock, so I guess this might make sense for the AD9102/AD9106 as well.

  -Ed