L4947

L4947R

5V-0.5A VERY LOW DROP REGULATOR WITH RESET

PRECISE OUTPUT VOLTAGE (5V

± 4%)

OVER FULL TEMPERATURE RANGE

(– 40 / 125

°C)

VERY LOW VOLTAGE DROP (0.75Vmax)

OVER FULL T RANGE

OUTPUT CURRENT UP TO 500mA

RESET FUNCTION

POWER-ON RESET DELAY PULSE DE-

FINED BY THE EXTERNAL CAPACITOR

+ 80V LOAD DUMP PROTECTION

– 80V LOAD DUMP PROTECTION

REVERSE VOLTAGE PROTECTION

SHORT CIRCUIT PROTECTION AND THER-

MAL SHUT-DOWN (with hysteresis)

LOW START UP CURRENT

DESCRIPTION

The L4947/L494 7R is a monolithic integrated cir-

cuit in Pentawatt package specially designed to

provide a stabilized supply voltage for automotive

and industrial electronic systems. Thanks to its

very low voltage drop, in automotive applications

the L4947/L4947R can work correctly even during

the cranking phase, when the battery voltage

could fall as low as 6V. Furthermore, it incorpo-

rates a complete range of protection circuits

against the dangerous overvoltages always pre-

sent on the battery rail of the car. The reset func-

tion makes the device particularly suited to supply

microprocessor based systems : a signal is avail-

able (after an externally programmable delay) to

reset the microprocessor at power-on phase ; at

power-off, this signal becomes low inhibiting the

microprocessor.

This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice.

June 2000

®

BLOCK DIAGRAM

Pentawatt

ORDERING NUMBERS: L4947

L4947R

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