Datasheet

TVP5146M2
www.ti.com
SLES141H JULY 2005 REVISED FEBRUARY 2012
5.2 Designing With PowerPAD Devices
The TVP5146M2 device is housed in a high-performance, thermally-enhanced, 80-terminal PowerPAD
package (TI package designator: 80PFP). Use of the PowerPAD package does not require any special
considerations except to note that the thermal pad, which is an exposed die pad on the bottom of the
device, is a metallic thermal and electrical conductor. Therefore, if not implementing the PowerPAD PCB
features, the use of solder masks (or other assembly techniques) may be required to prevent any
inadvertent shorting by the exposed thermal pad of connection etches or vias under the package. The
recommended option, however, is not to run any etches or signal vias under the device, but to have only a
grounded thermal land as explained in the following paragraphs. Although the actual size of the exposed
die pad may vary, the minimum size required for the keep-out area for the 80-terminal PFP PowerPAD
package is 8 mm × 8 mm.
It is recommended that there be a thermal land, which is an area of solder-tinned copper, under the
PowerPAD package. The thermal land varies in size, depending on the PowerPAD package being used,
the PCB construction, and the amount of heat that needs to be removed. In addition, the thermal land may
or may not contain numerous thermal vias depending on PCB construction.
Other requirements for using thermal lands and thermal vias are detailed in the TI application report
PowerPAD Thermally Enhanced Package (SLMA002), available via the TI web site at http://www.ti.com.
For the TVP5146M2 device, this thermal land must be grounded to the low-impedance ground plane of
the device. This improves not only thermal performance but also the electrical grounding of the device. It
is also recommended that the device ground terminal landing pads be connected directly to the grounded
thermal land. The land size must be as large as possible without shorting device signal terminals. The
thermal land may be soldered to the exposed thermal pad using standard reflow soldering techniques.
While the thermal land can be electrically floated and configured to remove heat to an external heat sink, it
is recommended that the thermal land be connected to the low-impedance ground plane for the device.
More information can be obtained from the TI application report PHY Layout (SLLA020).
Copyright © 20052012, Texas Instruments Incorporated Application Information 101
Submit Documentation Feedback
Product Folder Link(s): TVP5146M2