LM137/LM337
Connection Diagrams
(Continued)
TO-220
Plastic Package
3-Lead SOT-223
00906734
Front View
Order Number LM337IMP
Package Marked N02A See NS Package Number MP04A
00906707
Front View
Order Number LM337T
See NS Package Number T03B
Application Hints
When a value for
θ
(H−A)
is found using the equation shown,
a heatsink must be selected that has a value that is less than
or equal to this number.
HEATSINKING SOT-223 PACKAGE PARTS
The SOT-223 (“MP”) packages use a copper plane on the
PCB and the PCB itself as a heatsink. To optimize the heat
sinking ability of the plane and PCB, solder the tab of the
package to the plane.
Figures 3, 4
show the information for the SOT-223 package.
assumes a
θ
(J−A)
of 75˚C/W for 1 ounce copper and
51˚C/W for 2 ounce copper and a maximum junction tem-
perature of 125˚C.
00906733
FIGURE 4. Maximum Power Dissipation vs. T
AMB
for
the SOT-223 Package
Please see AN1028 for power enhancement techniques to
be used with the SOT-223 package.
00906732
FIGURE 3.
θ
(J−A)
vs Copper (2 ounce) Area for the
SOT-223 Package
5
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