S5U1284 SECOS [SeCoS Halbleitertechnologie GmbH], S5U1284 Datasheet - Page 4

• Manufacturer Part Number: S5U1284
• Description: 4A Ultra Low Dropout Positive Adjustable or Fixed-Mode Regulator
• Manufacturer: SECOS [SeCoS Halbleitertechnologie GmbH]

S5U1284
4A Ultra Low Dropout
Elektronische Bauelemente
Positive Adjustable or Fixed-Mode Regulator
Thermal Design
The S5U1284-XX incorporates an internal thermal shutdown that protects the device when the junction temperature
exceeds the maximum allowable junction temperatures. Although this device can operate with junction temperatures in the
range of 150 : , it is recommended that the selected heat sink be chosen such that during maximum continuous load
operation, the junction temperature is kept below this number. The example below shows the steps in selecting the proper
surface mount package.
Assuming, the following conditions: Vout =2.5V, Vin =3.3V, Vctrl =5V, Iout =2A DC Avg.
Calculate the maximum power dissipation using the following equation: Pd =Iout*(Vin-Vout) + (Iout/60)*(Vctrl-Vout)
Pd =2*(3.3-2.5) + (2/60)*(5-2.5) =1.68W
Using table below select the proper package and the amount of copper board needed.
Package
Copper Area
( /W)
:
Max Pd (Ta=25 ) :
Max Pd (Ta=45 ) :
JA
TO-263-5L
Pad Size 1.4” * 1.4”
25 ~ 45
2.4W ~ 4.4W
2.0W ~ 3.6W
Note: Above table is based on the max. junction temperature of 135 C.
o
Characteristics Curve
http://www.SeCoSGmbH.com/
Any changing of specification will not be informed individual
01-Jun-2002 Rev. A
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