LMX2581: LMX2581, 0_delay_mode, 2nd Order Modulator.

Richard gjensen

Part Number: LMX2581

Hi.

I have been using the LMX2581 for a while and now i need to use the 0 delay mode, for phase alignment between the input and output

It works fine for "integer mode", but i wold like to use it for "FRAC_ORDER = 2nd Order Modulator".

I can not get the signals to align properly.

My preferred numbers is 50Mhz inn, 868Mhz out, but i have tried all kind of numbers.

So my question is: Is this even possible to do with this chip?. If not do you have a chip that will do this.

Best regards

Richard

over 4 years ago

0 Liam Keese over 4 years ago

TI__Genius 12705 points

Hello Richard,

Yes, this zero delay function of feeding back the divider output should work in fractional or integer mode.

Did you also try first order modulator?

If you are using the TICS Pro GUI, the N divider would need to be adjusted by a factor of the VCO_DIV to compensate for the output divider as the GUI does not take this into account.

Regards,

0 Richard gjensen over 4 years ago in reply to Liam Keese

Prodigy 20 points

Hi,

First order modulator works.

Thanks so much for your time.

Regards,

Richard

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LMX2581: LMX2581, 0_delay_mode, 2nd Order Modulator.