3.0A Ultra Low Dropout Linear Regulator
TJ3966
Characteristic
Symbol
Rating
Unit
Maximum Allowable Power Dissipation at TA=25°C / SOP8-PP
Maximum Allowable Power Dissipation at TA=25°C / TO252
Maximum Allowable Power Dissipation at TA=25°C / TO263
Maximum Allowable Power Dissipation at TA=25°C / TO220
PDMax -SOP8-PP
PDMax -TO252
PDMax -TO263
PDMax -TO220
0.571
0.952
1.250
1.429
W
W
W
W
- Please note that above maximum allowable power dissipation is based on the minimum copper
plane area which does not exceed the proper footprint of the package. And the ambient
temperature is 25°C.
If proper cooling solution such as heat sink, copper plane area, air flow is applied, the maximum
allowable power dissipation could be increased. However, if the ambient temperature is increased, the
allowable power dissipation would be decreased.
For example, in case of TO263 package, θJA-TO263 is 80 °C/W, however, as shown in below graph, θJA
could be decreased with respect to the copper plane area. So, the specification of maximum power
dissipation for an application is fixed, the proper copper plane area could be estimated by following
graphs. As shown in graph, wider copper plane area leads lower θJA.
The maximum allowable power dissipation is also influenced by the ambient temperature. With the
above θJA-Copper plane area relationship, the maximum allowable power dissipation could be evaluated
with respect to the ambient temperature. As shown in graph, the higher copper plane area leads θJA.
And the higher ambient temperature leads lower maximum allowable power dissipation.
Aug. 2010 - Rev. 1.7.1
- 10 -
HTC