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DP++ mux with AD8197B or ADV3002

Question asked by rftoday on Jul 3, 2018
Latest reply on Jul 6, 2018 by PoornimaSubramani

We are looking to multiplex 10 DP++ ports into 1 DP port, and then convert to HDMI. (Or the following description might also convert to HDMI as well)
Looking to use 3 AD8197B 4:1 HDMI/DVI Switch with Equalization chips or possibly 3 ADV3002 4:1 HDMI/DVI Switch with Equalization DDC/CEC Buffers and EDID Replication chips.
Will have a 2 stage cascade of the parts or can have a single stage, both data sheets say:
"Outputs can be set to a high impedance state to reduce the power dissipation and/or to allow the construction of larger arrays using the wire-OR technique"

Distance will only be about a maximum of 3 feet.


From HDMI Wiki:
"The DisplayPort connector is compatible with HDMI and can transmit single-link DVI and HDMI 1.2/1.4/2.0
signals using attached passive adapters or adapter cables.[189][182][189] The source device includes
a dual-mode transmitter that supports both LVDS signals for DisplayPort and TMDS signals for DVI/HDMI.
The same external connector is used for both protocols - when a DVI/HDMI passive adapter is attached,
the transmitter circuit switches to TDMS mode."

Will the AD8197B or ADV3002 act as the "passive adapter" and signal the source to transmit as TMDS for the AD8197B or ADV3002?
Or do I force the DP signal CONFIG1 (DP_HDMI_MODE_DET_N) to a 1, to signal that an HDMI receiver is attached, to transmit TMDS signals?

The AD8197B supports up to 2.25 Gbps, so I would expect to run only at Reduced Bit Rate (RBR) of 1.62 Gbps that the DP port offers.
The ADV3002 says: Supports 250 Mbps to 2.25 Gbps data rates and beyond.
Not sure what "and beyond" signifies.

Are there any voltage, timing, jitter, or other issues?

Thank you in advance.

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