The shutdown that is thermal within the junction is prevented by an IC heat from rising high enough to harm the component (see Figure). This might be performed by monitoring the die temperature and reducing power that is interior to put the warmth on at the restricting value (usually about 160°C).

Circuit Operation:

The warmth sensor (Q1) is located close to the charged power transistor concerning the die, to assure tracking that is really close is thermal. R1 and R2 offer the base of Q1 at about 0.35V, which corresponds towards the turn-on VBE of Q1 at a temperature of about 160°C. As the die heat increases, Q1 in the course of time reaches the turn-on threshold(about 160°C), and starts pulling current far from the origin that is materials being current to your energy stage. The stress up-to-date is paid off (or take down entirely) which decreases the charged power that is internal for the regulator this way. In circumstances where thermal restricting occurs, both the output present and voltage will likely be paid off. As soon as the production voltage falls below its value that is mistake that is appearing that is nominal the voltage mistake amplifier might cause it so that they can correct the regulator manufacturing voltage by driving its production high (and sourcing more current towards the pass transistor). The limitation that is thermal can sink most of the present through the error amplifier manufacturing, and keep carefully the regulator manufacturing voltage/current as little as needed to match the junction temperature at 160°C. As shown, the limiter that is override that is thermal the voltage control cycle whenever needed seriously to avoid injury to the IC.