SOFT-START

The LM2614 has soft start to reduce current inrush during

power-up and startup. This reduces stress on the LM2614

and external components. It also reduces startup transients

on the power source. Soft start is implemented by ramping

up the reference input to the error amplifier of the LM2614 to

gradually increase the output voltage.

THERMAL SHUTDOWN PROTECTION

The LM2614 has a thermal shutdown protection function to

protect itself from short-term misuse and overload condi-

tions. When the junction temperature exceeds 150˚C the

device turns off the output stage and when the temperature

drops below 130˚C it initiates a soft start cycle. Prolonged

operation in thermal shutdown conditions may damage the

device and is considered bad practice.

VCON Transient Response

(Circuit in Figure 4)

20036719

FIGURE 8.

VCON Transient Response in Dropout

(Circuit in Figure 4)

20036720

FIGURE 9.

Load Transient Response

(Circuit in Figure 3)

20036727

FIGURE 10.

Line Transient Response

(Circuit in Figure 3)

20036728

FIGURE 11.

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