This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

DS125DF111: about output Clock

Part Number: DS125DF111
Other Parts Discussed in Thread: DS125DF410, DS110DF410

Hi:

There is a 10.3125Gbps rate signal access the input ,I want to the DS125DF111 output the clock recovery,how to set it?

  • Greetings,

    Please note register 0x1E[7:5] in the data sheet. Setting 0x1E[7:5] to 3'b011 or 3'b010 would enable Q and I clock. Please note this is not tested in production.

    Regards,, Nasser

  • Dear Nasser;

    I have confirmed to set 0x1E[7:5] t0 011 or 010,The output pin is still data.

    If it doesn't support this. Do TI have any other IC support clock recovery and Data rate support  1.25Gbps~11.3Gbps?

    Regards.

  • Greetings,

    1). Please note in additiona to setting reg 0x1E[7:5], you also need to set reg 0x9[5]. Was this done?

    2). You can also consider DS125DF410. Please note table 6 of this device data sheet. Here is a link to this part's data sheet:

    https://www.ti.com/lit/ds/symlink/ds125df410.pdf?ts=1599666798758&ref_url=https%253A%252F%252Fwww.ti.com%252Fsitesearch%252Fdocs%252Funiversalsearch.tsp%253FsearchTerm%253Dds125df410

    Regards,, Nasser

  • Dear Nasser;

    1). I reconfirmed DS125DF111,output the internal 10 MHz clock is ok,but can't output Q and I Clock;

    10MHz clock output seting:

    WIIC 0x30 0xff 0x05
    WIIC 0X30 0X09 0X20
    WIIC 0X30 0X1E 0XA0

    result is a clock 9Mhz

    Q-clock output seting:

    WIIC 0x30 0xff 0x05
    WIIC 0X30 0X09 0X20
    WIIC 0X30 0X1E 0X60

    result is a voltage 1.5V

    I-clock output seting:

    WIIC 0x30 0xff 0x05
    WIIC 0X30 0X09 0X20
    WIIC 0X30 0X1E 0X40

    result is a voltage 1.5V

    other question,what is Q and I clock?The clock come from input Data? 

    2) I don't have DS125DF410,now.

    Regards.

  • Greetings,

    1). I checked and DS125DF111 cannot output recovered clock. I/Q clock are the line recovered clock.

    2). As noted in the DS125DF410 data sheet, this part can provide line recovered VCO clock. Please note these are not tested in production.

    However, given you are not using DS125DF410, your present design based on DS125DF111 cannot support this feature.

    Regards,, Nasser

  • Greeting:

    I have DS110DF410,I checked the DS,I/Q clock functions is the same with DS125DF410,I will test DS110F410 as soon as possible

    Best regards!

  • Greetings,

    I've  tested DS110DF410,There is a signal input, but can't output the Q-clock,what's the setting wrong?Can you hele me?

    This is setting file

    Q-clock.cfg

    Regards,, 

  • Hi Andysss,

    Reviewed your register settings and it seems device is locked and thus we should be able to output I/Q clock as noted in table 6 of the data sheet. Let's do this:  First please make sure channel 0 is locked and then set reg 0x09[5]=1'b1. Further, try settings reg 0x1E[7:5]=3'b010. You can also try setting reg 0x09[7:0]=0x49.

    Regards,, Nasser

  • Dear Nasser,

    I'm sure  there is a singal locked in channel 0,the Locked LED is on and Reg 0x02=0xDC

    I have tested set Reg 0x09[7:0]=0x20 or 0x09[7:0]=0x49, 0x1E[7:0]=0x49,but can't output the clock

    Is there any other Reg need to setting?

  • Hi Nasser

    Do you have any other suggestions about output the Q/I clock?

    Best regards!

  • Greetings,

    We have checked this in the lab below and register settings below would generate the recovered clock:

    The channel register write routine below should work 

    REG       Value    Mask     Comment

    09           20           20           //Over-ride PFD Mux

    1e           40           e0           //Bring out eye clock from PFD to driver

    Please make sure you have these settings and the device is locked(i think this is the case based on your earlier report).

    Regards,, Nasser

  • Greetings,

    We have tested it again, input data rate  is 1.25Gbps and pattern is PRBS 7/23/31;

    There is a video, in the video 8 seconds before we set output 10M clock is ok and last two seconds we set output I‘clock is fail

    There is any picture/video/log about the test, We can't find out what's wrong

    1E-49.cfg

    1E_40.cfg

    This picture is test DS110DF410 output  The eye diagram

    Best regards..

  • Dear Nasser:

    Do you have the cfg file which is generate the recovered clock in the lab?

    We want to load it and check whether there is some settings is different

    Regard.

  • Hi Bear,

    We are getting one of these evaluation boards so we can check this. We are expecting to have a result by end of the week.

    Regards,, Nasser

  • Greetings,

    We ran a test in lab -channel 0 - and please below note 10GHz eye diagram and register settings. We used the same register settings that we had recommended earlier.

    Regards,, NasserRX Recovered Clock CH0.cfg

  • Greetings,

    You tested input data is 10Gbps or 1.25Gbps?

    If the input data is 1.25Gbps, is the output clock 1.25Ghz or 10Ghz? We need to output 1.25Ghz clock, is the IC supported? If not, is there any other IC to divide the clock by 8?

    Regards!

  • Greetings,

    Device can output clock either at 10GHz or 1.25GHz. Earlier, i showed 10GHz recovered clock and below is 1.25GHz recovered clock.

    Regards,, Nasser

     

  • Hi Nasser,

    The IC is very perfect,but we still haven't found out the problem about us.

    We need more informatin,As follows

    1. We think the extract clock functions DS125DF410 is same to DS110DF410,so,we tested IC is DS110DF410,and you?

    2.Does it mean that the input signal is 10.3125Gbps ,either at 1.289Ghz or 10.3125G clock can be output? What are the register settings different for the two Freq clock?

    3.Can you share more detailed information about conditions, steps,methods,pictures,video and more?

    The more the better,We will try our best to find out our problems.

    Thank you very much!

  • Greetings,

    1). Yes i checked DS110DF410 as well.

    2). Yes i used either 10.3125Gbps or 1.25Gbps PRBS15 signals and confirmed device is locked and then was able to output recovered clock.

    3). In the earlier post, i also included .cfg file. This file has the exact register settings which were used.

    Regards,, nasser

  • Greetings,

    Can it setting up the clock amplitude?

  • Greetings,

    Yes. But please note at 10GHz or 20Gbps there will high loss due to pcb and the media.

    Regards,, Nasser

  • Hi Nasser,
    Thank you very much!We have solved the problem.
    There are some other questions about the retimer.
    1) The retimer start with standard mode "Ethernet", is there a way for it to automatically switch modes based on the input data.for example,when the input data is 1.25Gbps auto switch to "Ethernet" and input data is 9.953Gbps auto switch to SDH/SONET.If not,How to setting the Retimer start with SDH/SONET after power off.
    2) There are 4 Pins indicating the locked state, Is there a function to assert signal detect?
    3) We want to the i-clock divider by 2(4 or 8 is ok).for example 10.3125Gbps data recovery 10.3125Ghz clock,we want the i-clock is 5.51625Ghz (2.278125Ghz or 1.289Ghz is ok) and the clock must synchronize with input data.
    4)earlier,you shared the Recovery 10Ghz clock,We noted the clock amplitude is only 130mVp-p, How to increase the amplitude through registers(compensation for high loss)?

    Best Regards..

  • Hi, see my inputs below to the four listed items.

    1. The retimer allows for the support of two separate VCO frequency groups simultaneously. Please refer to DS125DF111 datasheet Section 7.5.1.11 "Rate and Subrate Setting"
    2. The DS125DF111 has a signal detect status observation bit. It is channel register 0x54[7]
    3. There is no clear question here
    4.  The recovered clock amplitude is fixed and not adjustable

     

    0x54

    00

    7

    0

    N

    R

    Signal Detect observation bit.

    6

    0

    EQ Limiting (CTLE Stage 3[2]) observation bit.

    5:2

    0000

    Reserved

    1

    0

    CDR Lock Interrupt

    0

    0

    Signal Detect Interrupt

    Cordially,

    Rodrigo Natal

    HSSC Applications Engineer

  • Hello, The question is about DS110DF410,not DS125DF111.I don't know why my account can't post a new question,so my question follow the item. Regards...
  • Hi,

    The DS110DF410 retimer does not have the signal detect observation bit that the DS125DF111 does, but it does have a signal detect interrupt. My other inputs apply to both DS110DF410 and DS125DF111, as these products share similar design/architecture/digital features.

    Cordially,

    Rodrigo Natal

    HSSC Applications Engineer