THS4140 Datasheet, PDF (20/24 Pages) Texas Instruments – HIGH SPEED FULLY DIFFERENTIAL I/O AMPLIFIERS

THS4140, THS4141
HIGHĆSPEED FULLY DIFFERENTIAL I/O AMPLIFIERS
SLOS320E − MAY 2000 − REVISED JANUARY 2004
PRINCIPLES OF OPERATION
general PowerPAD design considerations
The THS414x 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 35(a) and Figure 35(b)]. This arrangement results in the lead frame being exposed as a
thermal pad on the underside of the package [see Figure 35(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.
More complete details of the PowerPAD installation process and thermal management techniques can be found
in the Texas Instruments Technical Brief, PowerPAD Thermally Enhanced Package (SLMA002). This document
can be found at the TI web site (www.ti.com) by searching on the key word PowerPAD. The document can also
be ordered through your local TI sales office. Refer to literature number SLMA002 when ordering.
DIE
Side View (a)
Thermal
Pad
DIE
End View (b)
Bottom View (c)
NOTE A: The thermal pad is electrically isolated from all terminals in the package.
Figure 35. Views of Thermally Enhanced DGN Package
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