THS4081, THS4082

175MHz LOW POWER HIGHSPEED AMPLIFIERS

SLOS274D − DECEMBER 1999 − REVISED JUNE 2001

16

POST OFFICE BOX 655303

APPLICATION INFORMATION

general PowerPAD

 design considerations

The THS408x is available packaged in a thermally-enhanced DGN package, which is a member of the

PowerPAD

 family of packages. This package is constructed using a downset leadframe upon which the die

is mounted [see Figure 44(a) and Figure 44(b)]. This arrangement results in the lead frame being exposed as

a thermal pad on the underside of the package [see Figure 44(c)]. Because this thermal pad has direct thermal

contact with the die, excellent thermal performance can be achieved by providing a good thermal path away

from the thermal pad.

The PowerPAD

 package allows for both assembly and thermal management in one manufacturing operation.

During the surface-mount solder operation (when the leads are being soldered), the thermal pad can also be

soldered to a copper area underneath the package. Through the use of thermal paths within this copper area,

heat can be conducted away from the package into either a ground plane or other heat dissipating device.

The PowerPAD

 package represents a breakthrough in combining the small area and ease of assembly of the

surface mount with the, heretofore, awkward mechanical methods of heatsinking.

DIE

Side View (a)

End View (b)

Bottom View (c)

DIE

Thermal

Pad

NOTE A: The thermal pad is electrically isolated from all terminals in the package.

Figure 44. Views of Thermally Enhanced DGN Package