LMX2592: PLLatinum Sim Simulated Values vs. TICSPro Implementation

Randy4TIics

Part Number: LMX2592
Other Parts Discussed in Thread: LMX2582

Hello folks,

We have been trying to implement a PLLatinum Sim LMX2592 simulation with the goal of getting the phase noise via loop filter/Kpd/divider values manipulation but the parameters obtained can't seem to be programmed properly into the LMX2592 with TICS Pro using both our own board and the LMX2582/92EVM board. Please see attached TICS Pro and PLLatinum Sim files and screen shots. The resulting tone from TICS Pro programming is ~6.98GHz instead of 8.490GHz, screenshot also attached. Any tricks on using the PLLatinum Sim and TICS Pro that we should know?

Thanks and regards,

Randy

over 3 years ago

0 Randy4TIics over 3 years ago

Prodigy 165 points

f8490MHz_test1.tcs

Somehow the PLLatinum Sim file can't be uploaded.

0 Noel Fung over 3 years ago in reply to Randy4TIics

TI__Guru** 107440 points

Hi Randy,

To get 200MHz fpd from a 100MHz reference clock, you should use the doubler instead of MULT.

When VCO doubler is used, prescalar has to be equal to 4. Given prescalar = 4, a 200MHz fpd will result in an invalid N-divider value of 10. So, you should reduce fpd to 100MHz in order to make N bigger.

If the Gain Multiplier is set to greater than x1.5, lock detect may not be working properly. We recommend make it equal x1 or x1.5.

Try the following configuration:

Clock & timing

Clock & timing forum

LMX2592: PLLatinum Sim Simulated Values vs. TICSPro Implementation