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LMK04828: single loop SYSREF 0-delay mode

Part Number: LMK04828
Other Parts Discussed in Thread: CODELOADER

two slave LMK(LMK_A and LMK_B) are in single loop SYSREF 0-delay mode, the SDCLKouts should be phase aligned with reference input after power-up,with a SYNC pulse,all the DCLKs and SDCLKs should be SYNCed.

now i can see the OSCout of two slave LMK are phase aligned and stable,SDCLKout of slave LMK_B are phase aligned with  OSCout too,those are what expected,

But OSCout_A are not phase aligned with SDCLKout of LMK_A?

the lock indicator LED is ON,and two slave LMKs are just the same, can this be a phase detector error?? or the chip is damaged ??

and SYNC_DISSYSREF bit must be enabled in SYSREF 0-delay  mode,am i wright?

even though SYNC PIN Disabled,SYNC_DISSYSREF enabled,toggling SYNC PIN can still reset phase of SDCLKs,why?? 

Thanks

  • Hi Min Hu
    Looks like an issue with outputs SYNC of the LMK_A. Can you send me your TICSpro config file? Please use File->Save and attach the saved file in the reply to this thread.
    Best regards
    Puneet
  • Hi,Punnet

    I use CodeLoader not TICSpro,below is the slave LMK reg values,both slave LMKs share the same values and the same configuration procedure,and I have also tested the  SYNC_PIN mode with CLKIN0_OUT_MUX = OFF and disable CLKIN0_EN.

    Thanks

    slave LMK register values export from CodeLoader4:

    R0 (INIT) 0x000090
    R0 0x000000
    R2 0x000200
    R256 0x010010
    R257 0x010155
    R259 0x010300
    R260 0x010422
    R261 0x010500
    R262 0x010672
    R263 0x010717
    R264 0x010810
    R265 0x010955
    R267 0x010B00
    R268 0x010C22
    R269 0x010D00
    R270 0x010E72
    R271 0x010F17
    R272 0x011010
    R273 0x011155
    R275 0x011300
    R276 0x011422
    R277 0x011500
    R278 0x011672
    R279 0x011717
    R280 0x011810
    R281 0x011955
    R283 0x011B00
    R284 0x011C22
    R285 0x011D00
    R286 0x011E72
    R287 0x011F17
    R288 0x012010
    R289 0x012155
    R291 0x012300
    R292 0x012422
    R293 0x012500
    R294 0x012672
    R295 0x012717
    R296 0x012810
    R297 0x012955
    R299 0x012B00
    R300 0x012C22
    R301 0x012D00
    R302 0x012E72
    R303 0x012F17
    R304 0x013010
    R305 0x013155
    R307 0x013300
    R308 0x013422
    R309 0x013500
    R310 0x013672
    R311 0x013717
    R312 0x013808
    R313 0x013900
    R314 0x013A00
    R315 0x013B10
    R316 0x013C00
    R317 0x013D08
    R318 0x013E03
    R319 0x013F15
    R320 0x014081
    R321 0x014100
    R322 0x014200
    R323 0x014310
    R324 0x014480
    R325 0x01457F
    R326 0x014609
    R327 0x01470C
    R328 0x014802
    R329 0x014902
    R330 0x014A02
    R331 0x014B16
    R332 0x014C00
    R333 0x014D00
    R334 0x014EC0
    R335 0x014F7F
    R336 0x015003
    R337 0x015102
    R338 0x015200
    R339 0x015300
    R340 0x015478
    R341 0x015500
    R342 0x015678
    R343 0x015700
    R344 0x015896
    R345 0x01593B
    R346 0x015A9B
    R347 0x015BD4
    R348 0x015C20
    R349 0x015D00
    R350 0x015E00
    R351 0x015F13
    R352 0x016000
    R353 0x016101
    R354 0x016228
    R355 0x016300
    R356 0x016400
    R357 0x016508
    R380 0x017C15
    R381 0x017D33
    R358 0x016600
    R359 0x016700
    R360 0x016801
    R361 0x016959
    R362 0x016A20
    R363 0x016B00
    R364 0x016C00
    R365 0x016D00
    R366 0x016E13
    R371 0x017300
    R8189 0x1FFD00
    R8190 0x1FFE00
    R8191 0x1FFF53

  • Hi Min Hu,
    Your configuration looks fine. In your previous post, you said that when the SYNC pin is dissabled and SYNC_DISSYSREF is also set, toggling the SYNC pin still effects the phase of the SDCLKs. This looks strange! Are the SDCLKs set to output SYSREF clocks or Device clocks?
    How do you toggle SYNC pin in this case, using Toggle SYNC_POL or you directly applying a SYNC edge on the PIN?
    Best regards
    Puneet
  • Hi,Puneet
    The LMKs are controled by Kintex7 FPGA,I use VIO to drive SYNC Pin directly.
    SDCLKs are set to output SYSREF clocks as the register settings above.
    SLave LMK SYNC Pin is disabled and SYNC_DISSYSREF is also set,I keep toggleing slave LMK's SYNC Pin dozens of times,the output clock phase may be changed once or more.
    it seems that there is not enough isolation between different SYNC Mode,but i am not sure.