ADV3000

Rev. 0 | Page 21 of 28

APPLICATION INFORMATION

Figure 31. Layout of the TMDS Traces on the ADV3000 Evaluation Board (Only Top Signal Routing Layer is Shown)

The ADV3000 is an HDMI/DVI switch, featuring equalized

TMDS inputs and pre-emphasized TMDS outputs. It is intended

for use as a 3:1 switch in systems with long cable runs on both

the input and/or the output, and is fully HDMI 1.3 receive-

compliant.

PINOUT

The ADV3000 is designed to have an HDMI/DVI receiver

pinout at its input and a transmitter pinout at its output. This

makes the ADV3000 ideal for use in AVR-type applications

where a designer routes both the inputs and the outputs directly

to HDMI/DVI connectors, as shown in Figure 31. When the

ADV3000 is used in receiver type applications, it is necessary to

change the order of the output pins on the PCB to align with the

on-board receiver.

One advantage of the ADV3000 in an AVR-type application is

that all of the high speed signals can be routed on one side (the

topside) of the board, as shown in Figure 31. In addition to

12 dB of input equalization, the ADV3000 provides up to 6 dB

of output pre-emphasis that boosts the output TMDS signals

and allows the ADV3000 to precompensate when driving long

PCB traces or output cables. The net effect of the input

equalization and output pre-emphasis of the ADV3000 is that

the ADV3000 can compensate for the signal degradation of

both input and output cables; it acts to reopen a closed input

data eye and transmit a full swing HDMI signal to an end

receiver. More information on the specific performance metrics

of the ADV3000 can be found in the Typical Performance

Characteristics section.

The ADV3000 also provides a distinct advantage in receive-type

applications because it is a fully buffered HDMI/DVI switch.

Although inverting the output pin order of the ADV3000 on the

PCB requires a designer to place vias in the high speed signal

path, the ADV3000 fully buffers and electrically decouples the

outputs from the inputs. Therefore, the effects of the vias placed

on the output signal lines are not seen at the input of the ADV3000.

The programmable output terminations also improve signal

quality at the output of the ADV3000. The PCB designer therefore

has significantly improved flexibility in the placement and

routing of the output signal path with the ADV3000 over other

solutions.