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LMK04828 PLL2 does not lock

toshi-e2e
Genius 4830 points
Other Parts Discussed in Thread: LMK04828, CODELOADER, DAC37J84EVM

Hi! all,

My customer reported that LMK04828 PLL2 does not lock.
And they try to change some constants of loopfilter2, but still PLL2 does not lock,　and CPout2 is 0V.

Their configulation is as follows.
Could you please advise how to solve this problem?

Regards,
Toshi

  • 0
    TI__Genius 10320 points

    Hi Toshi,

    Is the device configured in dual PLL mode or is only PLL2 being used? If you could provide a .mac file generated by codeloader, we can further debug this issue.

    Is this being done on the EVM? What VCXO or reference to PLL2 is being used?

    Gabe

  • 0 in reply to Gabe Ayala
    Genius 4830 points

    Hi, Gobe-san,

    Thanks  for your support.

    Now, they are evaluating LMK04828 on both their own designed board and the DAC37J84EVM.
    In case of DAC37J84EVM, they used onboard 122.88MHz VCOX and OSCin is 122.88MHz. 
    And when the PDF is set to 30.72MHz (as attached file [lmk04828test_PDF2_30720khz .mac]), the PLL2 did not lock.
    The Loopfilter2 cosntant is as follows;
     R2=1.2k,  R3= 0.2k R4=0.2k
     C1=27pF, C2=10pF, C3=10pF

    When the PFD is set to 61.44MHz (as attached file [lmk04828test_PDF2_61440khz.mac]) with the same Loopfilter2 constant,
    the PLL2 locked. 

    I changed the attached file extention from .mac to .txt due to the E2E system.
    So, after downloading the files, please change the file extention.

    Regards,
    Toshi

    Fullscreen lmk04828test_PDF2_30720khz.txt Download 
    [SETUP]
ADDRESS=888
CLOCK=1
DATA=2
LE=3
PART=LMK04828B
PINPOSITION00=1
PINPOSITION01=1
PINPOSITION02=1
PINPOSITION03=1
PINPOSITION04=1
[MODES]
NAME00=R0 (INIT)
VALUE00=144
NAME01=R0
VALUE01=16
NAME02=R2
VALUE02=512
NAME03=R256
VALUE03=65556
NAME04=R257
VALUE04=65877
NAME05=R259
VALUE05=66305
NAME06=R260
VALUE06=66562
NAME07=R261
VALUE07=66816
NAME08=R262
VALUE08=67313
NAME09=R263
VALUE09=67413
NAME10=R264
VALUE10=67596
NAME11=R265
VALUE11=67925
NAME12=R267
VALUE12=68352
NAME13=R268
VALUE13=68610
NAME14=R269
VALUE14=68864
NAME15=R270
VALUE15=69361
NAME16=R271
VALUE16=69381
NAME17=R272
VALUE17=69640
NAME18=R273
VALUE18=69973
NAME19=R275
VALUE19=70400
NAME20=R276
VALUE20=70658
NAME21=R277
VALUE21=70912
NAME22=R278
VALUE22=71417
NAME23=R279
VALUE23=71424
NAME24=R280
VALUE24=71704
NAME25=R281
VALUE25=72021
NAME26=R283
VALUE26=72448
NAME27=R284
VALUE27=72706
NAME28=R285
VALUE28=72960
NAME29=R286
VALUE29=73457
NAME30=R287
VALUE30=73523
NAME31=R288
VALUE31=73736
NAME32=R289
VALUE32=74069
NAME33=R291
VALUE33=74496
NAME34=R292
VALUE34=74754
NAME35=R293
VALUE35=75008
NAME36=R294
VALUE36=75513
NAME37=R295
VALUE37=75520
NAME38=R296
VALUE38=75784
NAME39=R297
VALUE39=76117
NAME40=R299
VALUE40=76544
NAME41=R300
VALUE41=76802
NAME42=R301
VALUE42=77056
NAME43=R302
VALUE43=77561
NAME44=R303
VALUE44=77568
NAME45=R304
VALUE45=77830
NAME46=R305
VALUE46=78165
NAME47=R307
VALUE47=78592
NAME48=R308
VALUE48=78850
NAME49=R309
VALUE49=79104
NAME50=R310
VALUE50=79601
NAME51=R311
VALUE51=79667
NAME52=R312
VALUE52=79877
NAME53=R313
VALUE53=80128
NAME54=R314
VALUE54=80396
NAME55=R315
VALUE55=80640
NAME56=R316
VALUE56=80896
NAME57=R317
VALUE57=81160
NAME58=R318
VALUE58=81411
NAME59=R319
VALUE59=81664
NAME60=R320
VALUE60=81935
NAME61=R321
VALUE61=82176
NAME62=R322
VALUE62=82432
NAME63=R323
VALUE63=82705
NAME64=R324
VALUE64=82944
NAME65=R325
VALUE65=83327
NAME66=R326
VALUE66=83480
NAME67=R327
VALUE67=83738
NAME68=R328
VALUE68=83970
NAME69=R329
VALUE69=84290
NAME70=R330
VALUE70=84482
NAME71=R331
VALUE71=84758
NAME72=R332
VALUE72=84992
NAME73=R333
VALUE73=85248
NAME74=R334
VALUE74=85696
NAME75=R335
VALUE75=85887
NAME76=R336
VALUE76=86019
NAME77=R337
VALUE77=86274
NAME78=R338
VALUE78=86528
NAME79=R339
VALUE79=86784
NAME80=R340
VALUE80=87160
NAME81=R341
VALUE81=87296
NAME82=R342
VALUE82=87672
NAME83=R343
VALUE83=87808
NAME84=R344
VALUE84=88214
NAME85=R345
VALUE85=88320
NAME86=R346
VALUE86=88696
NAME87=R347
VALUE87=89044
NAME88=R348
VALUE88=89120
NAME89=R349
VALUE89=89344
NAME90=R350
VALUE90=89600
NAME91=R351
VALUE91=89867
NAME92=R352
VALUE92=90112
NAME93=R353
VALUE93=90372
NAME94=R354
VALUE94=90788
NAME95=R355
VALUE95=90880
NAME96=R356
VALUE96=91136
NAME97=R357
VALUE97=91404
NAME98=R380
VALUE98=97301
NAME99=R381
VALUE99=97587
NAME100=R358
VALUE100=91648
NAME101=R359
VALUE101=91904
NAME102=R360
VALUE102=92176
NAME103=R361
VALUE103=92505
NAME104=R362
VALUE104=92704
NAME105=R363
VALUE105=92928
NAME106=R364
VALUE106=93184
NAME107=R365
VALUE107=93440
NAME108=R366
VALUE108=93715
NAME109=R371
VALUE109=94976
NAME110=R8189
VALUE110=2096384
NAME111=R8190
VALUE111=2096640
NAME112=R8191
VALUE112=2096979
OSCIN00=122.88
EXTRA_PLL_N_DIV_1_00=1
OSCIN01=122.88
EXTRA_PLL_N_DIV_1_01=1
PINS=0
[BURST]
COUNT=0
[FLEX]
CLKout0_FREQ=122.88
CLKout10_FREQ=307.2
CLKout11_FREQ=307.2
CLKout12_FREQ=409.6
CLKout13_FREQ=409.6
CLKout1_FREQ=122.88
CLKout2_FREQ=204.8
CLKout3_FREQ=204.8
CLKout4_FREQ=307.2
CLKout5_FREQ=307.2
CLKout6_FREQ=102.4
CLKout7_FREQ=102.4
CLKout8_FREQ=307.2
CLKout9_FREQ=307.2
DCLKout0_DIV_ud=DCLKout0_DIV
DCLKout10_DIV_ud=DCLKout10_DIV
DCLKout12_DIV_ud=DCLKout12_DIV
DCLKout2_DIV_ud=DCLKout2_DIV
DCLKout4_DIV_ud=DCLKout4_DIV
DCLKout6_DIV_ud=DCLKout6_DIV
DCLKout8_DIV_ud=DCLKout8_DIV
OSCout_FREQ=122.88
PLL2_PDF=30.72
SYSREF_freq=0.8
VCO_freq=2457.6
VCXO_freq=122.88
sync_SYSREF_freq=0.8
sync_VCO_freq=2457.6
[FLEXHASH]
HASHVALUE=11587216
    Fullscreen lmk04828test_PDF2_61440khz.txt Download 
    [SETUP]
ADDRESS=888
CLOCK=1
DATA=2
LE=3
PART=LMK04828B
PINPOSITION00=1
PINPOSITION01=1
PINPOSITION02=1
PINPOSITION03=1
PINPOSITION04=1
[MODES]
NAME00=R0 (INIT)
VALUE00=144
NAME01=R0
VALUE01=16
NAME02=R2
VALUE02=512
NAME03=R256
VALUE03=65556
NAME04=R257
VALUE04=65877
NAME05=R259
VALUE05=66305
NAME06=R260
VALUE06=66562
NAME07=R261
VALUE07=66816
NAME08=R262
VALUE08=67313
NAME09=R263
VALUE09=67413
NAME10=R264
VALUE10=67596
NAME11=R265
VALUE11=67925
NAME12=R267
VALUE12=68352
NAME13=R268
VALUE13=68610
NAME14=R269
VALUE14=68864
NAME15=R270
VALUE15=69361
NAME16=R271
VALUE16=69381
NAME17=R272
VALUE17=69640
NAME18=R273
VALUE18=69973
NAME19=R275
VALUE19=70400
NAME20=R276
VALUE20=70658
NAME21=R277
VALUE21=70912
NAME22=R278
VALUE22=71417
NAME23=R279
VALUE23=71424
NAME24=R280
VALUE24=71704
NAME25=R281
VALUE25=72021
NAME26=R283
VALUE26=72448
NAME27=R284
VALUE27=72706
NAME28=R285
VALUE28=72960
NAME29=R286
VALUE29=73457
NAME30=R287
VALUE30=73523
NAME31=R288
VALUE31=73736
NAME32=R289
VALUE32=74069
NAME33=R291
VALUE33=74496
NAME34=R292
VALUE34=74754
NAME35=R293
VALUE35=75008
NAME36=R294
VALUE36=75513
NAME37=R295
VALUE37=75520
NAME38=R296
VALUE38=75784
NAME39=R297
VALUE39=76117
NAME40=R299
VALUE40=76544
NAME41=R300
VALUE41=76802
NAME42=R301
VALUE42=77056
NAME43=R302
VALUE43=77561
NAME44=R303
VALUE44=77568
NAME45=R304
VALUE45=77830
NAME46=R305
VALUE46=78165
NAME47=R307
VALUE47=78592
NAME48=R308
VALUE48=78850
NAME49=R309
VALUE49=79104
NAME50=R310
VALUE50=79601
NAME51=R311
VALUE51=79667
NAME52=R312
VALUE52=79877
NAME53=R313
VALUE53=80128
NAME54=R314
VALUE54=80396
NAME55=R315
VALUE55=80640
NAME56=R316
VALUE56=80896
NAME57=R317
VALUE57=81160
NAME58=R318
VALUE58=81411
NAME59=R319
VALUE59=81664
NAME60=R320
VALUE60=81935
NAME61=R321
VALUE61=82176
NAME62=R322
VALUE62=82432
NAME63=R323
VALUE63=82705
NAME64=R324
VALUE64=82944
NAME65=R325
VALUE65=83327
NAME66=R326
VALUE66=83480
NAME67=R327
VALUE67=83738
NAME68=R328
VALUE68=83970
NAME69=R329
VALUE69=84290
NAME70=R330
VALUE70=84482
NAME71=R331
VALUE71=84758
NAME72=R332
VALUE72=84992
NAME73=R333
VALUE73=85248
NAME74=R334
VALUE74=85696
NAME75=R335
VALUE75=85887
NAME76=R336
VALUE76=86019
NAME77=R337
VALUE77=86274
NAME78=R338
VALUE78=86528
NAME79=R339
VALUE79=86784
NAME80=R340
VALUE80=87160
NAME81=R341
VALUE81=87296
NAME82=R342
VALUE82=87672
NAME83=R343
VALUE83=87808
NAME84=R344
VALUE84=88214
NAME85=R345
VALUE85=88320
NAME86=R346
VALUE86=88696
NAME87=R347
VALUE87=89044
NAME88=R348
VALUE88=89120
NAME89=R349
VALUE89=89344
NAME90=R350
VALUE90=89600
NAME91=R351
VALUE91=89867
NAME92=R352
VALUE92=90112
NAME93=R353
VALUE93=90370
NAME94=R354
VALUE94=90788
NAME95=R355
VALUE95=90880
NAME96=R356
VALUE96=91136
NAME97=R357
VALUE97=91404
NAME98=R380
VALUE98=97301
NAME99=R381
VALUE99=97587
NAME100=R358
VALUE100=91648
NAME101=R359
VALUE101=91904
NAME102=R360
VALUE102=92168
NAME103=R361
VALUE103=92505
NAME104=R362
VALUE104=92704
NAME105=R363
VALUE105=92928
NAME106=R364
VALUE106=93184
NAME107=R365
VALUE107=93440
NAME108=R366
VALUE108=93715
NAME109=R371
VALUE109=94976
NAME110=R8189
VALUE110=2096384
NAME111=R8190
VALUE111=2096640
NAME112=R8191
VALUE112=2096979
OSCIN00=122.88
EXTRA_PLL_N_DIV_1_00=1
OSCIN01=122.88
EXTRA_PLL_N_DIV_1_01=1
PINS=0
[BURST]
COUNT=0
[FLEX]
CLKout0_FREQ=122.88
CLKout10_FREQ=307.2
CLKout11_FREQ=307.2
CLKout12_FREQ=409.6
CLKout13_FREQ=409.6
CLKout1_FREQ=122.88
CLKout2_FREQ=204.8
CLKout3_FREQ=204.8
CLKout4_FREQ=307.2
CLKout5_FREQ=307.2
CLKout6_FREQ=102.4
CLKout7_FREQ=102.4
CLKout8_FREQ=307.2
CLKout9_FREQ=307.2
DCLKout0_DIV_ud=DCLKout0_DIV
DCLKout10_DIV_ud=DCLKout10_DIV
DCLKout12_DIV_ud=DCLKout12_DIV
DCLKout2_DIV_ud=DCLKout2_DIV
DCLKout4_DIV_ud=DCLKout4_DIV
DCLKout6_DIV_ud=DCLKout6_DIV
DCLKout8_DIV_ud=DCLKout8_DIV
OSCout_FREQ=122.88
PLL2_PDF=61.44
SYSREF_freq=0.8
VCO_freq=2457.6
VCXO_freq=122.88
sync_SYSREF_freq=0.8
sync_VCO_freq=2457.6
[FLEXHASH]
HASHVALUE=11587216

  • 0 in reply to toshi-e2e
    Genius 4830 points
    Hi, Gobe-san,
    I found out that my customer made a mistake in register setting.
    Also, I confirmed LMK04828 PLL2 locked on both their board and the EVM.
    I apologize to you for having made wasteful time by this item.

    Best regards,
    Toshi
  • 0 in reply to toshi-e2e
    TI__Genius 10320 points

    Toshi-san,

    No worries, that's what we are here for - to support you!

    Gabe

  • 0 in reply to toshi-e2e
    Prodigy 50 points

    Hi,Toshi

    I have use LMK04828B in only PLL2 mode. The PLL2_LD is not lock and and CPout2 is 0V.I don't know if I have a mistake in  register setting.

    Can you help me location the problem.

    Best regards,

    Liang

    Fullscreen 6862.lmk04828.mac.txt Download 
    [SETUP]
ADDRESS=888
CLOCK=1
DATA=2
LE=3
PART=LMK04828B
PINPOSITION00=1
PINPOSITION01=1
PINPOSITION02=1
PINPOSITION03=1
PINPOSITION04=1
[MODES]
NAME00=R0 (INIT)
VALUE00=144
NAME01=R0
VALUE01=16
NAME02=R2
VALUE02=512
NAME03=R256
VALUE03=65574
NAME04=R257
VALUE04=65859
NAME05=R259
VALUE05=66305
NAME06=R260
VALUE06=66627
NAME07=R261
VALUE07=66832
NAME08=R262
VALUE08=67072
NAME09=R263
VALUE09=67345
NAME10=R264
VALUE10=67640
NAME11=R265
VALUE11=67874
NAME12=R267
VALUE12=68352
NAME13=R268
VALUE13=68610
NAME14=R269
VALUE14=68864
NAME15=R270
VALUE15=69120
NAME16=R271
VALUE16=69393
NAME17=R272
VALUE17=69688
NAME18=R273
VALUE18=69922
NAME19=R275
VALUE19=70400
NAME20=R276
VALUE20=70658
NAME21=R277
VALUE21=70912
NAME22=R278
VALUE22=71168
NAME23=R279
VALUE23=71441
NAME24=R280
VALUE24=71718
NAME25=R281
VALUE25=72003
NAME26=R283
VALUE26=72448
NAME27=R284
VALUE27=72771
NAME28=R285
VALUE28=72960
NAME29=R286
VALUE29=73216
NAME30=R287
VALUE30=73489
NAME31=R288
VALUE31=73766
NAME32=R289
VALUE32=74051
NAME33=R291
VALUE33=74496
NAME34=R292
VALUE34=74819
NAME35=R293
VALUE35=75008
NAME36=R294
VALUE36=75264
NAME37=R295
VALUE37=75537
NAME38=R296
VALUE38=75814
NAME39=R297
VALUE39=76099
NAME40=R299
VALUE40=76544
NAME41=R300
VALUE41=76867
NAME42=R301
VALUE42=77056
NAME43=R302
VALUE43=77312
NAME44=R303
VALUE44=77585
NAME45=R304
VALUE45=77862
NAME46=R305
VALUE46=78147
NAME47=R307
VALUE47=78592
NAME48=R308
VALUE48=78915
NAME49=R309
VALUE49=79104
NAME50=R310
VALUE50=79360
NAME51=R311
VALUE51=79633
NAME52=R312
VALUE52=79909
NAME53=R313
VALUE53=80130
NAME54=R314
VALUE54=80396
NAME55=R315
VALUE55=80640
NAME56=R316
VALUE56=80896
NAME57=R317
VALUE57=81160
NAME58=R318
VALUE58=81409
NAME59=R319
VALUE59=81664
NAME60=R320
VALUE60=81920
NAME61=R321
VALUE61=82176
NAME62=R322
VALUE62=82432
NAME63=R323
VALUE63=82706
NAME64=R324
VALUE64=83057
NAME65=R325
VALUE65=83327
NAME66=R326
VALUE66=83456
NAME67=R327
VALUE67=83736
NAME68=R328
VALUE68=83970
NAME69=R329
VALUE69=84226
NAME70=R330
VALUE70=84482
NAME71=R331
VALUE71=84738
NAME72=R332
VALUE72=84992
NAME73=R333
VALUE73=85248
NAME74=R334
VALUE74=85696
NAME75=R335
VALUE75=85887
NAME76=R336
VALUE76=86019
NAME77=R337
VALUE77=86274
NAME78=R338
VALUE78=86528
NAME79=R339
VALUE79=86784
NAME80=R340
VALUE80=87160
NAME81=R341
VALUE81=87296
NAME82=R342
VALUE82=87672
NAME83=R343
VALUE83=87808
NAME84=R344
VALUE84=88214
NAME85=R345
VALUE85=88320
NAME86=R346
VALUE86=88696
NAME87=R347
VALUE87=89044
NAME88=R348
VALUE88=89120
NAME89=R349
VALUE89=89344
NAME90=R350
VALUE90=89600
NAME91=R351
VALUE91=89867
NAME92=R352
VALUE92=90112
NAME93=R353
VALUE93=90369
NAME94=R354
VALUE94=90662
NAME95=R355
VALUE95=90880
NAME96=R356
VALUE96=91136
NAME97=R357
VALUE97=91404
NAME98=R380
VALUE98=97301
NAME99=R381
VALUE99=97587
NAME100=R358
VALUE100=91648
NAME101=R359
VALUE101=91904
NAME102=R360
VALUE102=92175
NAME103=R361
VALUE103=92509
NAME104=R362
VALUE104=92704
NAME105=R363
VALUE105=92928
NAME106=R364
VALUE106=93184
NAME107=R365
VALUE107=93440
NAME108=R366
VALUE108=93715
NAME109=R371
VALUE109=94976
NAME110=R8189
VALUE110=2096384
NAME111=R8190
VALUE111=2096640
NAME112=R8191
VALUE112=2096979
OSCIN00=122.88
EXTRA_PLL_N_DIV_1_00=1
OSCIN01=100
EXTRA_PLL_N_DIV_1_01=1
PINS=0
[BURST]
COUNT=0
[FLEX]
CLKout0_FREQ=500
CLKout10_FREQ=500
CLKout11_FREQ=500
CLKout12_FREQ=500
CLKout13_FREQ=500
CLKout1_FREQ=500
CLKout2_FREQ=125
CLKout3_FREQ=125
CLKout4_FREQ=125
CLKout5_FREQ=125
CLKout6_FREQ=500
CLKout7_FREQ=500
CLKout8_FREQ=500
CLKout9_FREQ=500
DCLKout0_DIV_ud=DCLKout0_DIV
DCLKout10_DIV_ud=DCLKout10_DIV
DCLKout12_DIV_ud=DCLKout12_DIV
DCLKout2_DIV_ud=DCLKout2_DIV
DCLKout4_DIV_ud=DCLKout4_DIV
DCLKout6_DIV_ud=DCLKout6_DIV
DCLKout8_DIV_ud=DCLKout8_DIV
OSCout_FREQ=100
PLL2_PDF=100
SYSREF_freq=.9765625
VCO_freq=3000
VCXO_freq=100
sync_SYSREF_freq=.9765625
sync_VCO_freq=3000
[FLEXHASH]
HASHVALUE=11587216
    Fullscreen lmk04828.txt Download 
    R0 (INIT)	0x000090
R0	0x000010
R2	0x000200
R256	0x010026
R257	0x010143
R259	0x010301
R260	0x010443
R261	0x010510
R262	0x010600
R263	0x010711
R264	0x010838
R265	0x010922
R267	0x010B00
R268	0x010C02
R269	0x010D00
R270	0x010E00
R271	0x010F11
R272	0x011038
R273	0x011122
R275	0x011300
R276	0x011402
R277	0x011500
R278	0x011600
R279	0x011711
R280	0x011826
R281	0x011943
R283	0x011B00
R284	0x011C43
R285	0x011D00
R286	0x011E00
R287	0x011F11
R288	0x012026
R289	0x012143
R291	0x012300
R292	0x012443
R293	0x012500
R294	0x012600
R295	0x012711
R296	0x012826
R297	0x012943
R299	0x012B00
R300	0x012C43
R301	0x012D00
R302	0x012E00
R303	0x012F11
R304	0x013026
R305	0x013143
R307	0x013300
R308	0x013443
R309	0x013500
R310	0x013600
R311	0x013711
R312	0x013825
R313	0x013902
R314	0x013A0C
R315	0x013B00
R316	0x013C00
R317	0x013D08
R318	0x013E01
R319	0x013F00
R320	0x014000
R321	0x014100
R322	0x014200
R323	0x014312
R324	0x014471
R325	0x01457F
R326	0x014600
R327	0x014718
R328	0x014802
R329	0x014902
R330	0x014A02
R331	0x014B02
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	0x015900
R346	0x015A78
R347	0x015BD4
R348	0x015C20
R349	0x015D00
R350	0x015E00
R351	0x015F0B
R352	0x016000
R353	0x016101
R354	0x016226
R355	0x016300
R356	0x016400
R357	0x01650C
R380	0x017C15
R381	0x017D33
R358	0x016600
R359	0x016700
R360	0x01680F
R361	0x01695D
R362	0x016A20
R363	0x016B00
R364	0x016C00
R365	0x016D00
R366	0x016E13
R371	0x017300
R8189	0x1FFD00
R8190	0x1FFE00
R8191	0x1FFF53

  • 0 in reply to liang liu67
    Genius 4830 points

    Hi Liang,
    Do you use the internal VCO1?
    If yes, please try to set "0" to PLL2_CP_POL of Register 0x169.
    The internal VCO requires the negative charge pump polarity to be selected.

    best regards,
    Toshi

  • 0 in reply to toshi-e2e
    Prodigy 50 points
    Hi Toshi,
    I just use PLL2 mode,OSCin is 100MHz.The outpout is 125MHz as I desire.
    I have set "0" to PLL2_CP_POL of Register 0x169.The PLL2 doesn't lock still.
    The voltage of CPout2 is 1.2Vpp. I am not sure if the loop filter paremeter setted is reasonable.Should I simulate the loop filter use TI Clock design tool?
    How to set the PLL2_CAL_N?

    best regards,
    Liang
  • 0 in reply to liang liu67
    Genius 4830 points
    Hi Liang,

    I found another problem.
    PLL2_XTAL_EN of Register 0x162 should be "0" because you selected internal VCO1.

    About loop filter,
    yes, you need to simulate the loop filter by using tools for improving jitters.

    About PLL2_CAL_N, you does not use the 0-dealy loop mode. So you can set the same value of PLL2_N to PLL2_CAL_N.

    Regards,
    Toshi
  • 0 in reply to toshi-e2e
    TI__Mastermind 28550 points
    Hello Liang,

    With this feedback, have you been able to resolve your lock issue?

    73,
    Timothy
  • 0 in reply to Timothy T
    Prodigy 50 points
    PLL2 does not lock still.