• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 46 subscribers
  • Views 692 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.

Sync on THS8135

ran cohen56951
Prodigy 110 points
Other Parts Discussed in Thread: THS8135, THS8200

Hi,

i would like to get 3 kind of Syncs on my board:

HS+VS

Composite Sync

Sync on Green

 

i was wandering if there is a recommended way of doing that.

for getting the HS+VS i guess i can use the SN74LVC2T45DCUT non-inverting bus transceiver

 

Thx & BR

Ran.

  • 0
    TI__Genius 16810 points

    Ran,

    If you are using 1.8V logic, you will need to use a 1.8V/5V level translator for digitial HS and VS generation.  We have used an SN74LVCT45 for this. Note that there is an 8 pixel clock latency throught the THS8135 DACs, so to align HS with the RGB, you will need to delay this in the digital source.

    For a digital composite sync you will need to use logic to combine the digital HS and VS.

    For SOG sync insertion you will need dedicated and correctly timed /Sync, Sync-T (if tri-level syncs are required), /Blank, and possibly M1 and M2 control logic depending on the desire operasting mode.  Attached are some slides that may help.

    For automatic SOG insertion directly from HS and VS inputs or embedded syncs you may want to look at the THS8200 triple DAC.

    THS8135 SonY Setup.ppt
  • 0 in reply to Larry Taylor
    Prodigy 110 points

    Thx Larry

    i can't find data on SN74LVCT45, are you sure there isn't a mistake on one of the letters?

    would i also need to level translate RGB and the other pins comming from the OMAP to the RGB encoder?

     

    btw, isn't there an already prepared schematics for these syncs?, seems something that many will use.

     

    Thx again & BR

    Ran.

  • 0 in reply to ran cohen56951
    TI__Genius 16810 points

    Ran,

    Try SN74LVC2T45DCUT.  The THS8135EVM schematic files are at  http://focus.ti.com/docs/toolsw/folders/print/ths8135evm.html.  The EVM has this level translator on it. The EVM trageted RGB graphics with separate HS and VS, so there is no control logic for sync insertion.

    The analog RGB output levels will not require translation.  The DACs are designed to directly drive a video load.

    - Larry