®
L4949E
MULTIFUNCTION VERY LOW DROP
VOLTAGE REGULATOR
OPERATING DC SUPPLY VOLTAGE RANGE
5V - 28V
TRANSIENT SUPPLY VOLTAGE UP TO 40V
EXTREMELY LOW QUIESCENT CURRENT
IN STANDBY MODE
HIGH PRECISION STANDBY OUTPUT VOLT-
AGE 5V±1%
OUTPUT CURRENT CAPABILITY UP TO
100mA
VERY LOW DROPOUT VOLTAGE LESS
THAN 0.5V
RESET CIRCUIT SENSING THE OUTPUT
VOLTAGE
PROGRAMMABLE RESET PULSE DELAY
WITH EXTERNAL CAPACITOR
VOLTAGE SENSE COMPARATOR
THERMAL SHUTDOWN AND SHORT CIR-
CUIT PROTECTIONS
BLOCK DIAGRAM
Minidip
SO8
SO20W (12+4+4)
ORDERING NUMBERS:
L4949E (Minidip)
L4949ED (SO8)
L4949EP (SO20W)
DESCRIPTION
The L4949E is a monolithic integrated 5V voltage
regulator with a very low dropout output and addi-
tional functions as power-on reset and input volt-
age sense. It is designed for supplying the micro-
computer controlled systems especially in
automotive applications.
V
Z
V
OUT
CT
V
S
PREREGULATOR 5V
2µ
+
RES
2V
REG
RESET
V
S
SI
SO
1.23V
REF
SENSE
1.23V
GND
D96AT219
June 2000
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STMICROELECTRONICS [ STMICROELECTRONICS ]
