• State
  • Locked Locked
  • Replies 4 replies
  • Subscribers 33 subscribers
  • Views 492 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.

TPD7S019

emin koc
Prodigy 50 points
Other Parts Discussed in Thread: TPD7S019

Hello

I want to use TPD7S019 for my VGA connector. I already have a different ESD device on my design and it only contains a zener diode and TVS diode arrays. I am wondering if TPD7S019 requires external AND gates for HSYNC and VSYNC pins. Does the buffer inside the chip do the same thing with the AND gate((((one of the AND gate's pin is connected to 5V and the other is connected to VSYNC or HSYNC pins coming from GPU. The output is connected to a VGA connector))))?

Another thing, I need 33ohm resistor between SYNC line and VGA connector for impedance matching, TPD7S019 provides 15ohm, 55ohm and 65 ohm options. Should I choose the chip with 15 ohm and add 18ohm resistor in series with SYNC_OUT pins?

Thanks for any help.

Emin

  • 0
    TI__Intellectual 2520 points

    Emin, I am looking into this and should have a response to you by tomorrow the latest.

    Vivek

  • 0 in reply to Vivek Shankar
    Prodigy 50 points

    Thanks, I'm waiting for it.

  • 0
    TI__Intellectual 2520 points

    Emin, 

    Another thing, I need 33ohm resistor between SYNC line and VGA connector for impedance matching, TPD7S019 provides 15ohm, 55ohm and 65 ohm options. Should I choose the chip with 15 ohm and add 18ohm resistor in series with SYNC_OUT pins?

    The typical value of the termination resistor is 15 ohm. however, it can vary marginally. many of our customers merely have a footprint for an external resistor. usually, the signal integrity is very good with the internal resistor itself. I would recommend to have a footprint on your schematic and try with 0 ohm/ 18 ohm/ 10 ohm external resistors.

    I want to use TPD7S019 for my VGA connector. I already have a different ESD device on my design and it only contains a zener diode and TVS diode arrays. I am wondering if TPD7S019 requires external AND gates for HSYNC and VSYNC pins. Does the buffer inside the chip do the same thing with the AND gate((((one of the AND gate's pin is connected to 5V and the other is connected to VSYNC or HSYNC pins coming from GPU. The output is connected to a VGA connector)))

    I dont understand why you'd need to use a AND gate. The internal architecture is shown in the datasheet. The functioning of the TPD device is similar if driven by an AND gate or your controller. If you need further assistance, you can email me your schematic and we can discuss that. 

    Vivek Shankar

    vivek-s@ti.com

  • 0 in reply to Vivek Shankar
    Prodigy 50 points

    Hi Vivek,

    I'll take the advice about the resistor, thanks. The reference design I was working on has that AND gate I mentioned above and I was asking about the AND gate because I didn't know what it was for until i discovered that it was for voltage level shifting that the TPD device already provides.

    Thank you very much for your help.