DR73-100-R datasheet(20/28 Pages) AD

20 / 28 page

ADP2300/ADP2301

Rev. 0 | Page 20 of 28

THERMAL CONSIDERATIONS

The ADP2300/ADP2301 store the value of the inductor current

only during the on time of the internal MOSFET. Therefore, a small

amount of power is dissipated inside the ADP2300/ADP2301

package, which reduces thermal constraints.

However, when the application is operating under maximum

load with high ambient temperature and high duty cycle, the

heat dissipated within the package may cause the junction

temperature of the die to exceed the maximum junction

temperature of 125°C. If the junction temperature exceeds

140°C, the regulator goes into thermal shutdown and recovers

when the junction temperature drops below 125°C.

The junction temperature of the die is the sum of the ambient

temperature of the environment and the temperature rise of the

package due to power dissipation, as indicated in the following

equation:

TJ = TA + TR

where:

TJ is the junction temperature.

TA is the ambient temperature.

TR is the rise in temperature of the package due to power

dissipation.

The rise in temperature of the package is directly proportional

to the power dissipation in the package. The proportionality

constant for this relationship is the thermal resistance from the

junction of the die to the ambient temperature, as shown in the

following equation:

TR = θJA × PD

where:

TR is the rise in temperature of the package.

θJA is the thermal resistance from the junction of the die to the

ambient temperature of the package.

PD is the power dissipation in the package.

DR73-100-R Fiches technique(PDF) 20 Page - Analog Devices