Functional description

L7986TA

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Doc ID 022098 Rev 3

condition the system finds a different equilibrium with higher current. For example, with

Equation 5

Figure 7.

Overcurrent protection

5.5

Enable function

The enable feature allows to put the device into standby mode. With the EN pin lower than

0.3 V the device is disabled and the power consumption is reduced to less than 30

μA. With

the EN pin lower than 1.2 V, the device is enabled. If the EN pin is left floating, an internal

pull-down ensures that the voltage at the pin reaches the inhibit threshold and the device is

5.6

Hysteretic thermal shutdown

The thermal shutdown block generates a signal that turns off the power stage if the junction

temperature goes above 150 °C. Once the junction temperature returns to about 120 °C, the

device restarts in normal operation. The sensing element is very close to the PDMOS area,

so ensuring an accurate and fast temperature detection.

I

OUT

V

IN

F

SW

*

⋅

V

F

T

ON_MIN

⁄

–

DRC

T

ON_MIN

⁄

()

R

DSON

DCR

+

() F

SW

*

⋅

+

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4.2A

==