LP3893ES-1.2 National Semiconductor, LP3893ES-1.2 Datasheet - Page 9

• Manufacturer Part Number: LP3893ES-1.2
• Description: IC,VOLT REGULATOR,FIXED,+1.2V,CMOS,SIP,5PIN,PLASTIC
• Manufacturer: National Semiconductor
• Type: Linearr

Specifications of LP3893ES-1.2

• Rohs Compliant: NO
• Package: 6TO-263
• Function: LDO
• Number Of Outputs: 1
• Input Voltage Range: 5.5 to 1.47 V
• Output Voltage: 1.2 V
• Maximum Output Current: 3 A
• Output Type: Fixed
• Accuracy: ±1.5 %
• Typical Dropout Voltage @ Current: 0.27@3A V
• Operating Temperature: -40 to 125 °C
• Polarity: Positive

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. The graph below shows a
curve for the θ
sizes, using a typical PCB with 1 ounce copper and no solder
mask over the copper area for heat sinking.
FIGURE 1. θ
JA
JA
of TO-263 package for different copper area
vs Copper (1 Ounce) Area for TO-263
package
(Continued)
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9
As shown in the graph below, increasing the copper area
beyond 1 square inch produces very little improvement. The
minimum value for θ
PCB is 32˚C/W.
Figure 2 shows the maximum allowable power dissipation
for TO-263 packages for different ambient temperatures,
assuming θ
ture is 125˚C.
FIGURE 2. Maximum power dissipation vs ambient
JA
temperature for TO-263 package
is 35˚C/W and the maximum junction tempera-
JA
for the TO-263 package mounted to a
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