Length of Trace (inch)

0

5

10

15

20

25

30

35

40

-30

-25

-20

-15

-10

-5

0

D009

6 mil Loss at 2.7 GHz

4 mil Loss at 2.7 GHz

6 mil Loss at 4.05 GHz

4 mil Loss at 4.05 GHz

25

TDP142

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SLLSEZ1C – SEPTEMBER 2017 – REVISED MAY 2019

Product Folder Links: TDP142

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9.2.2.2 Detailed Design Procedure

The design procedure for Sink application is listed as follows:

•

Determine the loss profile on the DP input (C) and output (D) channels and cables. See Figure 20 for 6 mil

trace insertion loss.

•

Based upon the loss profile, determine the optimal configuration for the TDP142, to pass electrical

compliance.

•

See Figure 19 for information of Sink application on using the AC coupling capacitors, control pin resistors,

and for recommended decouple capacitors from VCC pins to ground.

–

AUX: AUXP has a 1 MΩ pull-up resistor and AUXN should have a 1 MΩ pull-down resistor. Theses 1 MΩ

resistors must be on the TDP142 side of the 100 nF capacitors.

–

HPDIN: The HPD signal should be routed to either pin 23 or pin 32 based on the GPIO/I2C mode. In that

way, the TDP142 will always be able to conserve power when a source is not connected.

Table 14. HPD GPIO/I2C Selection

MODE

HPD

GPIO (I2C_EN = 0)

Pin 32

I2C (I2C_EN != 0)

Pin 23

spacer

•

Configure the TDP142 using the GPIO terminals or the I2C interface:

–

GPIO – Using the terminals DPEQ0 and DPEQ1.

–

It is recommended to start a higher equalization value like 13 dB and 15 dB first and adjust the value if

necessary.

–

I2C - Refer to the I2C Register Maps and the Programming section for a detail configuration procedures.

•

The thermal pad must be connected to ground.

9.2.3 Application Curve

Figure 20. Insertion Loss of FR4 PCB Traces

10 Power Supply Recommendations

The TDP142 is designed to operate with a 3.3-V power supply. Levels above those listed in the Absolute

Maximum Ratings table should not be used. If using a higher voltage system power supply, a voltage regulator

can be used to step down to 3.3 V. Decoupling capacitors should be used to reduce noise and improve power

supply integrity. A 0.1-µF capacitor should be used on each power pin.