L4947PD

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 L4947PD is a monolithic integrated circuit in

HiPSO package specially designed to provide a

stabilized supply voltage for automotive and in-

dustrial electronic systems. Thanks to its very low

voltage drop, in automotive applications the

L4947PD can work correctly even during the

cranking phase, when the battery voltage could

fall as low as 6V. Furthermore, it incorporates a

complete range of protection circuits against the

dangerous overvoltages always present on the

battery rail of the car. The reset function makes

the device particularly suited to supply microproc-

essor based systems : a signal is available (after

an externally programmable delay) to reset the

microprocessor at power-on phase ; at power-off,

this signal becomes low inhibiting the microproc-

essor.

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

June 2000

®

DUMP

PROTECT.

START

REF.

THERMAL

PROTECTION

RESET

CIRCUIT

ERROR

AMP.

OUTPUT

CURRENT

LIMITER

ANTI

SAT.

PNP OUTPUT

TRANSISTOR

D94AT106

17

1-20

INPUT

DELAY CAPACITOR

2

OUTPUT

3

RESET

OUTPUT

19

GROUND

1-20

BLOCK DIAGRAM

PowerSO20

ORDERING NUMBER: L4947PD

1/6