PIN CONNECTION (Top view)

FUNCTIONAL DESCRIPTION

The operating principle of the voltage regulator is

basedon thereference,the error amplifier,the driver

and the power PNP. This stage uses an Isolated

Collector Vertical PNP transistor which allows to ob-

tain very low dropout voltage (typ. 450mV) and low

Thanks to these features the device is particularly

suited when the power dissipation must be limited

as, for example, in automotive or industrial applica-

tions supplied by battery.

The three gain stages (operational amplifier,

driver and power PNP) require the external capaci-

µF) to guarantee the global stability

of the system.

The antisaturationcircuit allows to reduce drastically

the current peak which takes place during the start

up.

The reset function is LOW active when the output

voltage level is lower than the reset threshold volt-

HIGH aftera delaytime settablewith the externalca-

µF.Thereset

and delay threshold hysteresis improve the noise

immunity allowing to avoid false switchings. The

typical reset output waveform is shown in fig. 1.

ABSOLUTE MAXIMUM RATINGS

Symbol

Parameter

Value

Unit

DC Input Voltage

35

V

DC Reverse Voltage

–18

V

Positive Load Dump Protection (t = 300ms)

60

V

Junction Temperature Range

–40 to 150

°C

Operating Temperature Range

–40 to 125

°C

Storage Temperature Range

–55 to 150

°C

THERMAL DATA

Symbol

Parameter

Value

Unit

Thermal Resistance Junction-case

Max.

3.5

°C/W

Note: T he circuit is ESD protected according to MIL-STD -883C

L4922

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