Other Parts Discussed in Thread: LMX2594, LMX2572
Hello,
I'm trying to experiment with the phase shifting functions of the LMX2572LP using the dev board and TICSPRO software. I have it set up to output 400MHz from the standard 100MHz reference it comes with. There's a section on phase shifting in the instruction manual for the eval kit (section 3.2.1 of http://www.ti.com/lit/ug/snau217b/snau217b.pdf). As far as I can see, my settings are the same as for the example given there, but I cannot see any phase shift on the 400 MHz output when I write the MASH_SEED value. As I understand it, writing this register should give a phase change if everything is set up properly.
I am measuring phase by looking at it on a scope. The scope is triggered on the 100MHz reference and because the output is an integer multiple of the reference, I can see the two signals together. I had expected that the output would shift relative to the input when I wrote values to MASH_SEED, but this is not happening. I’ve attached a screenshot of the TICSPRO window to show my current settings. Is there something I’m missing here?
Thanks,
Gordon.