1.5A Ultra Low Dropout Linear Regulator
TJ3965
Characteristic
Symbol
θJA-MSOP8
θJA-SOP8
Rating
Unit
Thermal Resistance Junction-To-Ambient / MSOP8
Thermal Resistance Junction-To-Ambient / SOP8
Thermal Resistance Junction-To-Ambient / SOP8-PP
Thermal Resistance Junction-To-Ambient / SOT223
Thermal Resistance Junction-To-Ambient / TO252
Thermal Resistance Junction-To-Ambient / TO263
Thermal Resistance Junction-To-Ambient / TO220
Thermal Resistance Junction-To-Ambient / SOT89
220
165
175
140
105
80
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
θJA-SOP8-PP
θJA-SOT223
θJA-TO252
θJA-TO263
θJA-TO220
θJA-SOT89
70
200
In case that there is no cooling solution and no heat sink / copper plane area for heat sink, the maximum
allowable power dissipation of each package is as follow;
Characteristic
Symbol
Rating
Unit
Maximum Allowable Power Dissipation at TA=25°C / MSOP8
Maximum Allowable Power Dissipation at TA=25°C / SOP8
PDMax-MSOP8
PDMax -SOP8
0.455
0.606
0.571
0.714
0.952
1.250
1.429
0.500
W
W
W
W
W
W
W
W
Maximum Allowable Power Dissipation at TA=25°C / SOP8-PP PDMax -SOP8-PP
Maximum Allowable Power Dissipation at TA=25°C / SOT223
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
Maximum Allowable Power Dissipation at TA=25°C / SOT89
PDMax -SOT223
PDMax -TO252
PDMax -TO263
PDMax -TO220
PDMax –SOT89
- 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 SOT223 and TO263 package, θJA-SOT223 is 140 °C/W and 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.
Jul. 2010 – Rev. 1.12
- 11 -
HTC