L4937N ,DUAL MULTIFUNCTION VOLTAGE REGULATORELECTRICAL CHARACTERISTICS (V = 14V; –40°C ≤ T ≤ 125°C unless otherwise specified)S jSymbol Paramet ..
L4937NL ,DUAL MULTIFUNCTION VOLTAGE REGULATOR®L4937NDUAL MULTIFUNCTION VOLTAGE REGULATOR. STANDBY OUTPUT VOLTAGE PRECISION 5V± 2%.OUTPUT 2 TRACK ..
L4937NL ,DUAL MULTIFUNCTION VOLTAGE REGULATORELECTRICAL CHARACTERISTICS (V = 14V; –40°C ≤ T ≤ 125°C unless otherwise specified)S jSymbol Paramet ..
L4938E ,ADVANCED VOLTAGE REGULATORapplications.PIN CONNECTIONSPR 1 20 SIGND 1 20 GNDPR 1 16 SICT 2 19 VS1N.C. 2 19 N.C.CT 2 15 VS1EN ..
L4938ED ,ADVANCED VOLTAGE REGULATORL4938E/EDL4938EPD®ADVANCED VOLTAGE REGULATORENABLE AND SENSE INPUTS (EN, SI) PRO-TECTED AGAINST NEG ..
L4938ED013TR ,ADVANCED VOLTAGE REGULATORELECTRICAL CHARACTERISTICS (V = 14V; T = -40 to 150°C unless otherwise specified.)S jSymbol Paramet ..
LBA120 , Dual Single-Pole OptoMOS Relay
LBA120 , Dual Single-Pole OptoMOS Relay
LBA120 , Dual Single-Pole OptoMOS Relay
LBA120. , Dual Single-Pole OptoMOS Relay
LBA120PTR , Dual Single-Pole OptoMOS Relay
LBA673 , Lead (Pb) Free Product - RoHS Compliant
L4937N
DUAL MULTIFUNCTION VOLTAGE REGULATOR
L4937NDUAL MULTIFUNCTION VOLTAGE REGULATOR STANDBY OUTPUT VOLTAGE PRECISION 5V
± 2%. OUTPUT 2 TRACKED TO THE STANDBY OUT-
PUT. OUTPUT 2 DISABLE FUNCTION FOR
STANDBY MODE. VERY LOW QUIESCENT CURRENT, LESS
THAN 250μA, IN STANDBY MODE. OUTPUT CURRENTS : I01 = 50mA, I02 = 500mA. VERY LOW DROPOUT (max 0.4V/0.6V). OPERATING TRANSIENT SUPPLY VOLTAGE
UP TO 40V. POWER-ON RESET CIRCUIT SENSING THE
STANDBY OUTPUT VOLTAGE. POWER-ON RESET DELAY PULSE DEFINED
BY THE EXTERNAL CAPACITOR. THERMAL SHUTDOWN AND SHORT CIRCUIT
PROTECTIONS
DESCRIPTIONThe L4937N is a monolithic integrated dual voltage
regulators with two very low dropout outputs and ad-
ditional functions such as power-on reset and input
voltage sense. It is designed for supplying micro-
computer controlled systems specially in automo-
tive applications.
PIN CONNECTION (top view)June 2000 1/9
BLOCK DIAGRAM
THERMAL DATA
L4937N2/9
ABSOLUTE MAXIMUM RATINGS
Note : The circuit is ESD protected according to MIL–STD–883C.
APPLICATION CIRCUIT
L4937N3/9
ELECTRICAL CHARACTERISTICS (VS = 14V; –40°C ≤ Tj ≤ 125°C unless otherwise specified)ENABLE
L4937N4/9
ELECTRICAL CHARACTERISTICS (continued)RESET
Note : 1 : VO2 connected to ADJ.VO2 can be set to higher values by inserting an external resistor divider.
2 : Foldback characteristic
FUNCTIONAL DESCRIPTIONThe L4937N is based on the SGS-THOMSON Mi-
croelectronics modular voltage regulator approach.
Several out-standing features and auxiliary func-
tions are provided to meet the requirements of sup-
plying the microprocessor systems used in automo-
tive applications.
Furthermore the device is suitable also in other ap-
plications requiring two stabilized voltages.
The modular approach allows other features and
functions to be realized easily when required.
STANDBY REGULATOR
The standby regulator uses an Isolated Collector
Vertical PNP transistor as the regulating element.
This structure allows a very low dropout voltage at
currents up to 50mA. The dropout operation of the
standby regulator is maintained down to 2V input
supply voltage. The output voltage is regulated up
to the transient input supply voltage of 40V. This fea-
ture avoids functional interruptions which could be
generated by overvoltage pulses.
The typical curve of the standby output voltage as
a function of the input supply voltage is shown in fig.
The current consumption of the device (quiescent
current) is less than 250μA when output 2 is dis-
abled (standby mode). The dropout voltage is con-
trolled to reduce the quiescent current peak in the
undervoltage region and to improve the transient
response in this region.
The quiescent current is shown in fig. 2 as a function
of the supply input voltage 2.
OUTPUT 2 VOLTAGE
The output 2 regulator uses the same output struc-
ture as the standby regulator, but rated for an output
current of 500mA.
The output 2 regulator works in tracking mode with
the standby output voltage as a reference voltage.
The output 2 regulator can be switched off via the
Enable input.
L4937N5/9
