Other Parts Discussed in Thread: LMK61E07
Dear all,
We found the measured phase noise of LMK61E2 is quite much worse than the datasheet, though at a different frequency.
Could someone explain that if this is expected, i.e. LMK61Exx is optimised for 156.25MHz in integer-N mode and 161.1328125MHz in Fractional-N mode, rather than 125MHz?
Please find our measurement attached, the LMK61E2 is set to 125MHz and 125.000001MHz to force configuration tool going into the fractional-N mode.
The configuration RAW registers values generated with the TI tool are the following.
For fractional-N mode:
R0 0x0010
R1 0x010B
R2 0x0233
R8 0x08B0
R9 0x0901
R16 0x1000
R17 0x1180
R21 0x1501
R22 0x1600
R23 0x172A
R25 0x1900
R26 0x1A34
R27 0x1B20
R28 0x1C00
R29 0x1D01
R30 0x1E3F
R31 0x1FFF
R32 0x20FF
R33 0x2103
R34 0x2224
R35 0x2327
R36 0x2424
R37 0x2502
R38 0x2600
R39 0x2707
R47 0x2F00
R48 0x3000
R49 0x3110
R50 0x3200
R51 0x3300
R52 0x3400
R53 0x3500
R56 0x3800
R72 0x4802
For Integer-N mode:
R0 0x0010
R1 0x010B
R2 0x0233
R8 0x08B0
R9 0x0901
R16 0x1000
R17 0x1180
R21 0x1501
R22 0x1600
R23 0x1728
R25 0x1900
R26 0x1A32
R27 0x1B00
R28 0x1C00
R29 0x1D00
R30 0x1E00
R31 0x1F00
R32 0x2001
R33 0x210C
R34 0x2228
R35 0x2303
R36 0x2408
R37 0x2500
R38 0x2600
R39 0x2700
R47 0x2F00
R48 0x3000
R49 0x3110
R50 0x3200
R51 0x3300
R52 0x3400
R53 0x3500
R56 0x3800
R72 0x4802
We also got similar result on LMK61E07, which we actually prefer to use, but the tool and evaluation board doesn't seem avaliable.
Please advise, thanks.
Regards,
Wade