eorex
EP1117
Figure 4-θ(JA) vs copper area for TO-252 package
The thermal resistance for each application will be affected by thermal interactions with other
components on the board. Some experimentation will be necessary to determine the actual value.
The power dissipation of EP1117 is equal to: PD = (VIN - VOUT) × IOUT
Maximum junction temperature is equal to: TJUNCTION = TAMBIENT + (PD × θ(JA)
Note: TJUNCTION must not exceed 125°C
)
Safe Operation Area
Using the experiment result of previous Thermal Consideration (choose the one with 1.5cm*1.5cm
polygene area) and θ(JA)=50°C/W spec, the safe operation area of EP1117 in SOT-223 and TO-252
packages can be obtained as Figure 5.
Figure 5-Safe Operation Area of EP1117 in SOT-223 and TO-252 packages
(Limited by Power Dissipation with TJUNCTION < 125°C)
Jul. 2006
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