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LMX2320 PLL minimun frequency

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albert22

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Hi,
I would like to use a LMX2320 in a frequency synthesizer with minimum freq around 50 or 60 Mhz.
I checked the datasheet and no minimum freq is specified for the 2320 or the 2315.
The same DS gives a min freq. of 1.2Ghz only for the 2325
However the input sensitivity curves start at 100Mhz for the 2315. And 1GHz for the 2320/25.
What would be the minimum frequency of operation for the 2320 ? .
Thanks
 

Data sheets seldom tell the fine points. The best thing to do is download the software for the evaluation board, and plug in your frequencies on the computer face. If the LMX2320 will accept the divisor values, the software will accept your inputs.

The problem is that there are "gaps" in divisor codes in some of these chips that are due to the way the prescalar and 1/n counter work, and you might find that your exact set of frequencies can not be supported.
 

Thanks biff44
I downloaded the Ti CodeLoader as you said. It seems to be very useful to configure and test a prototype. Regrettably when I select any of the PLLs in the menu the program gives a "Runtime error 13 - type mismatch" and cancels. I will try to make it work later.
Anyway I am not concerned about divisor codes but in the minimum frequency that the fin prescaler will correctly divide. The counters and the divider are fine for my frequency range and step.
Specifications of the LMX family only say that they work "up to XX Ghz" suggesting that the fin pin could be used from DC up to xx Ghz but I find this hard to believe.
 
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