The "shadow" video problem of TVP7002.

SuitJune Young

Genius 3985 points

Other Parts Discussed in Thread: TVP7002

Hello,TIer.

We using TVP7002 and DM8168 together to capture VGA video.

but now,we foung that the captured video has a shadow in some position.

Just like the picture below:

we can see the shadow of a black bar inside the red circule.

What may cause the problem?

I have tried modify the phase register of TVP7002.but no effect.

The RC delay circuit have beed added for Vsync of TVP7002.

Thanks for any reply.

over 10 years ago

0 Steve Clynes over 10 years ago

TI__Mastermind 43875 points

First, are you 100% sure this is a capture issue and not a display issue? How are you displaying the image?

Second, this type of smearing is usually caused by bad analog cable impedance matching. Plese make sure that your source is good, your cables are good quality and that the analog input circuit to the TVP7002 is correct and impedance matched. Make sure that the input termination is correct and that the coupling capacitors are the correct value.

Make sure that the TVP7002 is correctly configured for the video mode you are sourcing. You can find example setup configurations on the TVP7002 EVM product folder on http://www.ti.com/tool/tvp7002evm.

BR,

Steve

0 SuitJune Young over 10 years ago in reply to Steve Clynes

Genius 3985 points

Thank,SIr.

I found the problem.It's the unmatch resistance problem.

0 Steve Clynes over 10 years ago in reply to SuitJune Young

TI__Mastermind 43875 points

Excellent. Glad you are OK now.

BR,

Steve

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The "shadow" video problem of TVP7002.