I've looked through and searched the AD9524 register documentation. I can find no reference to a bypass PLL2 mode but somehow my device seems to be in this mode. I'm using the eval. board to control the AD9524 in my design by jumpering over the 4 SPI lines and resetb. This works fine and I have full control through the eval software. However, my output frequency is not what is expected or what is reported by the eval SW. I have a 125 MHz VCXO. I'm targeting for a 4 GHz VCO to divide to 1 GHZ and then to 40 MHz with /25 each output divider. Instead I'm getting a solid 5 MHz that does not change no matter what I do to PLL2. This happens on output4 not just output0 and output1 so it is not the bypass mux available for these output[0,1]. Changing the VCO frequency by changing the N divider or doubler as no effect on the output frequency. Syncing the output dividers, resetting the device and reloading the stp file, powering down/up PLL2 all these have no effect. The frequency remains unchanged at 5 MHz which is 125/25
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I have also discovered a bug with the eval software. When I click on the output3 control icon the program crashes and aborts. I tried this several times with the same result. I ended up having to manually edit my stp file just to set the output to the proper mode.
