ADV739x: Video Encoder outout circuit

Hi,

  As per expert comment, We can use series capacitors to completely block the DC current flow through the signal path (The Cap is a DC blocking cap).

 The series capacitors block this DC offset and the input pin will bias the signal that is acceptable to the part.
 Also we can remove DC-Offset with a high-pass filter.

 Kindly refer here at (+) ADV7393: DC Offset on Output of DAC1 - Q&A - Video - EngineerZone (analog.com)

 Note: External filter and buffer components connected to the DAC outputs should be placed as close as possible to the ADV7390/ ADV7391/ADV7392/ADV7393 to minimize the possibility of noise pickup from neighboring circuitry and to minimize the effect of trace capacitance on output bandwidth. 

Thanks,

Poornima

Hi,

  As per expert comment, We can use series capacitors to completely block the DC current flow through the signal path (The Cap is a DC blocking cap).

 The series capacitors block this DC offset and the input pin will bias the signal that is acceptable to the part.
 Also we can remove DC-Offset with a high-pass filter.

 Kindly refer here at (+) ADV7393: DC Offset on Output of DAC1 - Q&A - Video - EngineerZone (analog.com)

 Note: External filter and buffer components connected to the DAC outputs should be placed as close as possible to the ADV7390/ ADV7391/ADV7392/ADV7393 to minimize the possibility of noise pickup from neighboring circuitry and to minimize the effect of trace capacitance on output bandwidth. 

Thanks,

Poornima

Hi,Poornima

Thank you for your response.　Let me check a little more.

Is the following understanding correct?

a) There is no problem in installing an AC coupling capacitor to the ADV7390 DAC output on the ADV7390 board as a stand-alone unit.

b) However, it is necessary to check/evaluate whether the receiving side (video decoder side) can receive/display the signal normally.

c) ADI cannot guarantee the operation of an AC coupling capacitor on the ADV7390 DAC output on the ADV7390 board, because it is outside the ADV7390 datasheet specifications.

If the above understanding is correct, we will reply to the customer based on it.

best regards
AimPoint.

Hi,

Please refer this thread (+) Short to Power Protection for ADV7180 and ADV7393 - Q&A - Video - EngineerZone (analog.com) Here expert given some suggestion regarding AC coupling.

Thanks,

Poornima

Hi,Poornima
Thank you for your response.
best regards
AimPoint.