• State
  • Locked Locked
  • Replies 3 replies
  • Subscribers 33 subscribers
  • Views 955 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.

Attenuation about DS92LV18 and SN65LVDS250

Satoshi
Guru 19645 points
Other Parts Discussed in Thread: DS92LV18, SN65LVDS250, DS10CP154A

Customer is evaluating DS92LV18.

In the case of between SN65LVDS250, attenuate is larger than DS92LV18 only.

Image and waveform is below,

①DS92LV18 ⇒ SN65LVDS250 ⇒ DS92LV18

　※Waveform point is "SN65LVDS250 ⇒ DS92LV18" line

②DS92LV18 ⇒ DS92LV18

【Question】

1. I think that this cause is bit error.

　Is this influence signal quality?

2. If yes, Is there way to control emphasis (or the other)?

3. Please let me know how to improve attenuation for ①.

Best regards,

Satoshi

  • 0
    TI__Mastermind 43795 points

    Hi Satoshi,

    The sharp edge rates in both oscilloscope waveforms indicate that attenuation or trace loss will not be an issue in this system.  Are you using the SN65LVDS250 for the crosspoint function only?  You could also consider the DS10CP154A crosspoint which includes built in termination resistors to save board space.

    Regards,

    Lee

  • 0 in reply to Lee Sledjeski
    Guru 19645 points
    Lee-san

    Thank you for reply.
    I will confirm customer for DS10CP154A.

    Additional question,
    Please let me know why the difference waveform between "SN65LVDS250 ⇒ DS92LV18" and "DS92LV18 ⇒ DS92LV18".
    (Transmission line, harness, and the other are the same)
    And, Is there way to control(or external device) emphasis or equalizer?

    Best regards,
    Satoshi
  • 0 in reply to Satoshi
    TI__Mastermind 43795 points

    Satoshi-san,

    The DS92LV18 output driver is specified to have a 500mV nominal VOD.  The LVDS250 device is only 350mV.  This is the reason why the signal is smaller with the LVDS250.  This smaller signal has enough amplitude to work with the DS92LV18 receiver.  In this case equalization of the signal should not be required. 

    Regards,

    Lee