PLL unlock problem(please help)

[HKYO]

pll unlock

my pll unlocks in specific voltage range about 10mV

ex) Freq. unlock voltage(+- 10 mV)
86oMHz 1.63
870MHz 1.65
. .
and this unlock voltage range changes when i change the

bias of 4/5 divider. also when temperature is -25 degrees C

unlock voltage range increases like 100mV. This symptom happens

when pll locks high frequency. Somebody please help me.

 

[VSWR]

unlock pll

Could be many reasons. WinRAR your design incl schematic diagram and upload here.