LP3966ES-2.5 National Semiconductor, LP3966ES-2.5 Datasheet - Page 15

• Manufacturer Part Number: LP3966ES-2.5
• Description: IC, LDO VOLT REG, 2.5V, 3A, TO-263-5
• Manufacturer: National Semiconductor

Specifications of LP3966ES-2.5

• Primary Input Voltage: 7V
• Output Voltage Fixed: 2.5V
• Dropout Voltage Vdo: 800mV
• No. Of Pins: 5
• Output Current: 3A
• Operating Temperature Range: -40°C To +125°C
• Termination Type: SMD
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Application Hints
HEATSINKING TO-263 PACKAGE
The TO-263 package uses the copper plane on the PCB as
a heatsink. The tab of these packages are soldered to the
copper plane for heat sinking. Figure 3 shows a curve for the
θ
a typical PCB with 1 ounce copper and no solder mask over
the copper area for heat sinking.
JA
FIGURE 3. θ
of TO-263 package for different copper area sizes, using
JA
vs Copper (1 Ounce) Area for TO-263
package
(Continued)
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As shown in the figure, increasing the copper area beyond 1
square inch produces very little improvement. The minimum
value for θ
32˚C/W.
Figure 4 shows the maximum allowable power dissipation
for TO-263 packages for different ambient temperatures,
assuming θ
ture is 125˚C.
FIGURE 4. Maximum power dissipation vs ambient
JA
JA
temperature for TO-263 package
for the TO-263 package mounted to a PCB is
is 35˚C/W and the maximum junction tempera-
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