[ LMX2582 ] ACAL_FAST setting and Lock Behavior

Kenichiro

Other Parts Discussed in Thread: LMX2582EVM, LMX2582

[ LMX2582 ] ACAL_FAST setting and Lock Behavior

Hi,

My customer has tested LMX2582EVM with its default setting (100MHz, default loop filter) and reported a bit strange behavior by checking/unchecking ACAL_FAST setting.

According to customer, LMX2582 occasionally fail to lock to input clock

ACAL_FAST checked: occasionally fail to lock
ACAL_FAST un-checked: successfully achieve lock

Have you seen this behavior before?
Thanks,
Ken

over 8 years ago

0 Julian Di Matteo over 8 years ago

TI__Expert 4085 points

Hi Ken,

We received your question. Thank you for your patience. I forwarded this post to the applications engineer most familiar with this device.

Regards,
Julian

0 Brian Wang over 8 years ago in reply to Julian Di Matteo

TI__Expert 8055 points

Ken,

What is your register writing sequence? You can have them send a ".tcs" file (File --> Save) so I can load in and check.

Regards,

Brian Wang

0 Kenichiro over 8 years ago in reply to Brian Wang

Mastermind 9165 points

Hi Brian,

Thank you for your response.
Please find out attached .tcs file.
(Since I cannot upload .tcs file onto E2E, I change it to .txt)

ACALFAST_ON.txt

[SETUP]
ADDRESS=888
CLOCK=8
DATA=4
LE=2
PART=LMX2582
ADDRESS_I2C=0x0

[PINS]
PINNAME00=CE
LOCATION00=7
PINVALUE00=True

[MODES]
NAME00=R64
VALUE00=4195247
NAME01=R61
VALUE01=3997697
NAME02=R59
VALUE02=3866624
NAME03=R48
VALUE03=3146748
NAME04=R47
VALUE04=3080384
NAME05=R46
VALUE05=3020195
NAME06=R45
VALUE06=2949170
NAME07=R44
VALUE07=2883584
NAME08=R43
VALUE08=2818048
NAME09=R42
VALUE09=2752512
NAME10=R41
VALUE10=2687076
NAME11=R40
VALUE11=2621440
NAME12=R39
VALUE12=2589188
NAME13=R38
VALUE13=2490416
NAME14=R37
VALUE14=2441216
NAME15=R36
VALUE15=2360337
NAME16=R35
VALUE16=2294299
NAME17=R34
VALUE17=2278384
NAME18=R33
VALUE18=2179600
NAME19=R32
VALUE19=2114064
NAME20=R31
VALUE20=2033153
NAME21=R30
VALUE21=1966132
NAME22=R29
VALUE22=1900676
NAME23=R28
VALUE23=1845540
NAME24=R24
VALUE24=1574153
NAME25=R23
VALUE25=1542210
NAME26=R22
VALUE26=1450752
NAME27=R20
VALUE27=1310820
NAME28=R19
VALUE28=1247589
NAME29=R14
VALUE29=918561
NAME30=R13
VALUE30=868352
NAME31=R12
VALUE31=815105
NAME32=R11
VALUE32=720920
NAME33=R10
VALUE33=659672
NAME34=R9
VALUE34=590594
NAME35=R8
VALUE35=528516
NAME36=R7
VALUE36=469170
NAME37=R4
VALUE37=268611
NAME38=R1
VALUE38=67592
NAME39=R0
VALUE39=8732

[FLEX]
CalculatedCPG=10
CalculatedKvco=34.2
CalculatedTotalDivide=2
Fosc_FREQ=100
FoutA_FREQ=2450
FoutB_FREQ=2450
Fpd_FREQ=100
Fvco_FREQ=4900
VCO_MULTIPLIED_FREQ=4900
btn_LoadRegisters=Load Registers
btn_SimplifyFraction=Simplify Fraction

Also, here is the screen shot of TICS pro. Procedure is simple.
Just turn on power supply for PLL, then perform "Write All Registers".

Thanks,
Ken

0 Kenichiro over 8 years ago in reply to Kenichiro

Mastermind 9165 points

Hi Brian,

Did you have a chance to look into this information?

Thanks,
Ken

0 Brian Wang over 8 years ago in reply to Kenichiro

TI__Expert 8055 points

ACALFAST_ON_fix.txt

[SETUP]
ADDRESS=888
CLOCK=8
DATA=4
LE=2
PART=LMX2592
ADDRESS_I2C=0x0

[PINS]
PINNAME00=CE
LOCATION00=7
PINVALUE00=True

[MODES]
NAME00=R64
VALUE00=4195247
NAME01=R62
VALUE01=4063232
NAME02=R61
VALUE02=3997697
NAME03=R59
VALUE03=3866624
NAME04=R48
VALUE04=3146748
NAME05=R47
VALUE05=3080384
NAME06=R46
VALUE06=3020195
NAME07=R45
VALUE07=2949170
NAME08=R44
VALUE08=2883584
NAME09=R43
VALUE09=2818048
NAME10=R42
VALUE10=2752512
NAME11=R41
VALUE11=2687076
NAME12=R40
VALUE12=2621440
NAME13=R39
VALUE13=2589188
NAME14=R38
VALUE14=2490416
NAME15=R37
VALUE15=2441216
NAME16=R36
VALUE16=2360337
NAME17=R35
VALUE17=2294299
NAME18=R34
VALUE18=2278394
NAME19=R33
VALUE19=2173450
NAME20=R32
VALUE20=2105610
NAME21=R31
VALUE21=2033153
NAME22=R30
VALUE22=1966132
NAME23=R29
VALUE23=1900676
NAME24=R28
VALUE24=1845540
NAME25=R25
VALUE25=1638400
NAME26=R24
VALUE26=1574153
NAME27=R23
VALUE27=1542210
NAME28=R22
VALUE28=1450752
NAME29=R20
VALUE29=1310820
NAME30=R19
VALUE30=1247589
NAME31=R14
VALUE31=918561
NAME32=R13
VALUE32=868352
NAME33=R12
VALUE33=815105
NAME34=R11
VALUE34=720920
NAME35=R10
VALUE35=659672
NAME36=R9
VALUE36=590594
NAME37=R8
VALUE37=528516
NAME38=R7
VALUE38=469170
NAME39=R4
VALUE39=268611
NAME40=R2
VALUE40=132352
NAME41=R1
VALUE41=67592
NAME42=R0
VALUE42=8732

[FLEX]
CalculatedCPG=10
CalculatedKvco=34.2
CalculatedTotalDivide=2
Fosc_FREQ=100
FoutA_FREQ=2450
FoutB_FREQ=2450
Fpd_FREQ=100
Fvco_FREQ=4900
VCO_MULTIPLIED_FREQ=4900
btn_LoadRegisters=Load Registers
btn_SimplifyFraction=Simplify Fraction

Ken,

I tried the script. After trying a few times it did lose lock. The reason is we have some internal settings not set right. The registers to change are below. And I also attached a tcs file in txt format

R32=0x210A

R33=0x2A0A

R34[4:0]=0xA

Regards,

Brian Wang

0 Kenichiro over 8 years ago in reply to Brian Wang

Mastermind 9165 points

Hi Brian,

Thank you for checking. Is this what you descried?
Is "R34[4:0]=0xA" right? R34[3:0]?

I will ask my customer to make sure the behavior with new script.
Thanks,
Ken

0 Kenichiro over 8 years ago in reply to Kenichiro

Mastermind 9165 points

Brian,

My customer has found the discrepancy of register value between datasheet and the raw registers you sent to me above.
Can you clarify which values are correct?

Thanks,
Ken

0 Brian Wang over 8 years ago in reply to Kenichiro

TI__Expert 8055 points

Hi Ken,

Use the bottom screen

R7[11]=1, R8[7]=1, R8[2]=1, R46[4]=0. The datasheet will update to match.

Also in your previous post, R34[4:0] = 0xA, so you also need that R34[4] to be 0.

Regards,

Brian Wang

0 Kenichiro over 8 years ago in reply to Brian Wang

Mastermind 9165 points

Thanks, Brian!

I wait for the datasheet being updated.

Regards,
Ken

Clock & timing

Clock & timing forum

[ LMX2582 ] ACAL_FAST setting and Lock Behavior

[ LMX2582 ] ACAL_FAST setting and Lock Behavior