• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 33 subscribers
  • Views 368 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

DS92LV16: Buffer Functionality

Moises Cruz
Prodigy 10 points
Part Number: DS92LV16

Hi,

I am a college student working on my senior design project and need help with using this component. In essence, the DS92LV16 will be used to serialize 16 bits coming from a Raspberry Pi 4 and feeding the serial stream to a laser that will hopefully achieve gigabit transmissions. My plan is to feed a clock source from the Raspberry Pi at 65 MHz, times 16 bits, the serializer will be able to achieve > 1 GHz transmission.

I am trying to find out if the DS92LV16 has some sort of buffer that will store the 16 bits of data, because while the RPi has a general purpose clock that can generate 65 MHz, the GPIO pins are not able to reach this clock frequency. So the clock will be running at a much higher frequency than the data that I am trying to transmit, which I am assuming will not work in the way I want it to. If there is no buffer available on the DS92LV16, what alternative could I pursue?

Thanks!

Morgan

  • 0
    TI__Guru 64326 points

    Hi Morgan,

    Keep in mind that you will be operating at ~1 Gbps not 1GHz on the "serial" side. DS92LV16 does not buffer and will serialize the "symbol" at its input based on TCLK. You may consider bit stuffing as a way to work around this limitation.  

  • 0 in reply to Malik Barton57
    Prodigy 10 points

    Hi Malik,

    Thanks for the response! I'm a little confused still since this is my first time working on a project where a constraint is high-speed data transmissions, and also working with serializers in general. My main concern is, if the TCLK input is 65 MHz but the data pins are not being updated at the same frequency (answers vary, but it seems like the maximum GPIO toggling rate of the Raspberry Pi is around 50 MHz), wouldn't I be transmitting redundant data? As in, new data is not being fed to be serialized quickly enough to be transmitted. Is this something the DS92LV16 would take care of? I'm not sure if I am explaining my issue as well as I should...

    Thanks for the help!

    Morgan

  • +1 in reply to Moises Cruz
    TI__Guru 64326 points

    Hi Morgan,

    You are asking the right questions. DS92LV16 does not have internal memory the buffer the incoming data packets on the parallel side. Without some formatting of the data you would be transmitting redundant data in the next packet. Put simply the DIN pin state would not change before the next rising edge of  TCLK.