STLQ50XX

Application information

11/18

7.3

Protection

case proper limiting network is recommended.

The current limitation is automatically provided by the characteristics of the PMOS pass

element (see typical characteristics), so the short circuit current is dependent on the input

voltage. When considering the short circuit current take care, in any case, to not exceed the

maximum power dissipation sustainable by the device.

The STLQ50 features an internal thermal protection that linearly reduces the output current

when the internal temperature increases, consequently, at a given load, also the output

voltage decreases. The action of the thermal protection starts at 125 °C when the output

voltage slightly decreases, while close to 163 °C the output voltage drops to 0 V. Since this

is a linear control, sudden over current conditions can quickly rise the chip temperature

without time for the thermal protection to act, so it cannot be used as a limitation for the

output current.