Datasheet

L4972A
L4972AD
January 1995
2A SWITCHING REGULATOR
.2A OUTPUT CURRENT
.5.1V TO 40V OUTPUT VOLTAGE RANGE
.0 TO 90% DUTY CYCLE RANGE
.INTERNAL FEED-FORWARD LINE REG.
.INTERNAL CURRENT LIMITING
.PRECISE 5.1V ± 2% ON CHIP REFERENCE
.RESET AND POWER FAIL FUNCTIONS
.INPUT/OUTPUT SYNC PIN
.UNDER VOLTAGE LOCK OUT WITH HYS-
TERETIC TURN-ON
.PWM LATCH FOR SINGLE PULSE PER PE-
RIOD
.VERY HIGH EFFICIENCY
.SWITCHING FREQUENCY UP TO 200KHz
.THERMAL SHUTDOWN
.CONTINUOUS MODE OPERATION
DESCRIPTION
TheL4972Ais a stepdownmonolithicpowerswitch-
ingregulatordelivering 2A ata voltagevariablefrom
5.1 to 40V.
Realized with BCD mixed technology, the device
uses a DMOS output transistor to obtain very high
efficiencyand veryfast switching times. Featuresof
BLOCK DIAGRAM
POWERDIP
(16 + 2 + 2)
the L4972A include reset and power fail for micro-
processors, feed forward line regulation, soft start,
limiting current and thermal protection. The device
is mountedin a Powerdip 16+2 +2 andSO20large
plastic packages and requires few external compo-
nents. Efficient operation at switching frequencies
up to 200KHz allows reductionin the size and cost
of external filter component.
ORDERING NUMBERS : L4972A (Powerdip)
L4972AD (SO20)
1/23
This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice.
SO20
MULTIPOWER BCD TECHNOLOGY