[ADV7390] "Optional Low Pass Filter" of Full Drive mode of ADV739x.

Hi,

We are checking with the expert. We will get back to you Once get the solution.

Thanks,

Varshini K

Hi,

Thank you for your reply.
I'm waiting for your feedback.

Thank you!
Best regards.
Tamu

Hi,

The optional (reconstruction (anti-imaging)) low pass filter is described in the section “VIDEO OUTPUT BUFFER AND OPTIONAL OUTPUT FILTER” at page 69

Please ensure with the above things and get back to us if further clarification is required on this.

Thanks,

Varshini K

Hi,

Thank you for your reply.

I think the section "VIDEO OUTPUT BUFFER AND OPTIONAL OUTPUT FILTER", "Figure 87", "Figure 88" and "Figure 89" at page 69 indicates optional low pass filter of Low-Drive mode.
These figures include an driver buffer IC. The driver buffer ICs are not required for Full-Drive mode.

I want to know the details of the "OPTIONAL LPF" recommended circuit of "Full Drive mode".
What kind of circuit do you recommend as the "OPTIONAL LPF" for "Full Drive mode" of ADV739x?

Thank you!
Best regards.
Tamu

Hi,

As per the expert comment,

This section mentioned 2 different items: [#1] video output buffer requirement for low-drive mode and [#2] Optional LPF for DAC output depending on application.

[#1] Customer needs to use video output buffer in low-drive mode. Full-drive mode does not require video output buffer.

[#2] If customer uses 16× (SD), 8× (ED), or 4× (HD) oversampling, LPF filter is not required. Otherwise. LPF may be required in other oversampling.

Customer can consider ADA4411-3 for integrated video filter buffers (combining filter and buffer funcitons).

Thanks,

Varshini K

Hi,

Thank you for your reply.

I understand what is described in the section "VIDEO OUTPUT BUFFER AND OPTIONAL OUTPUT FILTER" of the datasheet you indicated.

What I want to know is the detail of the "OPTIONAL LPF" recommended circuit of "Full Drive mode".
What kind of circuit do you recommend as the "OPTIONAL LPF" for "Full Drive mode" of ADV739x?

If you don't have any your recommended circuit, that's OK, please let me know it.

Thank you!
Best regards.
Tamu

Hi,

As per the expert comment,

We recommend 3 different options for optional LPF in full-drive mode.

[#1] Avoid LPF by using 16× (SD), 8× (ED), or 4× (HD) oversampling configuration from Table 57.

[#2] Implement LPF circuit that meets the requirement in Table 58. Example circuits are shown in Figures 87-89.

[#3] Consider ADA4411-3 for integrated video filter buffers.

 We does not have other recommendation for optional LPF in full-drive mode.

Thanks,

Varshini K

Hi,

Thank you for your reply.

I think the [#1] is how to avoid optional LPF by using 16× (SD), 8× (ED), or 4× (HD) oversampling configuration.
And I think the [#2] and [#3] are not for optional LPF in Full-Drive mode but for in Low-Drive mode because these include external output buffers such as ADA4411-3.

So I think you don't have your recommended circuit for optional LPF in Full-Drive mode.
Is this my understanding correct?
If this is correct, I'll tell it to the customer, and this question thread will be closed.

Thank you!
Best regards.
Tamu

Hi,

We does not have other recommendation for optional LPF in full-drive mode.

Thanks,

Varshini K

Thank you!