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LMK04803: How to use same loop filter for two different frequency requierment

Part Number: LMK04803
Other Parts Discussed in Thread: LMK61E2, , LMK04610

Hi,

 

In our clock tree, we are using LMK04803B and LMK61E2.

LMK04803B is provided with reference clock (of 125MHz LVDS by default) from LMK61E2.

 

Our system is having two operating modes M0 and M1. Either only one mode M0 or M1 will be active at a time. So we have two different set of frequency requirement for M0 and M1

M0 will operate with following clock frequencies

  1. 200MHz LVDS      x 1 Number
  2. 2.5MHz LVDS      x 1 Number
  3. 40MHz LVDS       x 2 Number

 

M1 will operate with following clock frequencies

  1. 200MHz LVDS        x 1 Number
  2. 3.5MHz LVDS         x 1 Number
  3. 56MHz LVDS           x 1 Number
  4. 40MHz LVDS           x 1 Number

Loop filter component values in my design is given below

C1=220nF, C2=10uF, R2=0.68K for Loop Filter 1

C1=6.8nF, C2=1.8nF, C3=0.01nF, C4=0.01nF, R2=0.82K, R3=0.2K, R4=0.2K for Loop Filter 2

The external VCXO preferred is CVHD-950-122.880 (having frequency 122.88MHz)

 

My questions is as follows

  1. Here M0 and M1 are having different clocking requirements. Can we implement the above specification in LMK04803B with same loop filter component and same external VCXO (having frequency 122.88MHz) for both modes M0 and M1?

Thank you..