TFP503

PanelBus HDCP DIGITAL RECEIVER

SLDS149 − AUGUST 2004

21

POST OFFICE BOX 655303

Data

A

S

Slave Address

Sub Address

A

WSr

A

P

From Transmitter

From Receiver

Sr Restart Condition

A

Acknowledge

S

Start Condition

P

Stop Condition

A

RA

Slave Address

Data

A

Not Acknowledge (SDA High)

W

Write

R

Read

Data

S

Slave Address

R

P

From Transmitter

From Receiver

R

Read

A

Acknowledge

S

Start Condition

P

Stop Condition

A

A

Not Acknowledge (SDA High)

A

Data

A

Figure 20. HDCP Port Link Integrity Message Read

make the output level marginal. The level shifter design must minimize loading and losses to provide the best

possible low level signal on the SDA line.

PowerPAD 100-terminal TQFP package

The TFP503 is packaged in TI’s thermally enhanced PowerPAD 100-terminal TQFP packaging. The PowerPAD

package is a 14-mm

× 14-mm × 1-mm TQFP outline with 0.5-mm lead-pitch. The PowerPAD package has a

specially designed die-mount pad that offers improved thermal capability over typical TQFP packages of the

same outline. The TI 100-terminal TQFP PowerPAD package offers a backside solder plane that connects

directly to the die-mount pad for enhanced thermal conduction. If traces or vias are located under the back side

pad, they must be protected by a suitable solder mask or other assembly technique to prevent inadvertent

shorting to the exposed backside pad.

Soldering the backside of the device to a thermal land connected to the PCB ground plane is recommended

for thermal, electrical, and EMI considerations. The thermal land may be soldered to the exposed PowerPAD

using standard reflow soldering techniques.

The recommended pad size for the grounded thermal land is 5.8 mm minimum, centered in the device land

pattern. When vias are required to ground the land, multiple vias are recommended for a low-impedance

connection to the ground plane. Multiple vias are also recommended when thermal flow from the land to another

plane is needed. Vias in the exposed pad must be small enough or filled to prevent wicking the solder away from

the interface between the package body and the thermal land on the surface of the board during solder reflow.