L4975A Datasheet, PDF (1/21 Pages) STMicroelectronics – 5A SWITCHING REGULATOR

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L4975A
5A SWITCHING REGULATOR
5A OUTPUT CURRENT
5.1V TO 40V OUTPUT VOLTAGE RANGE
0 TO 90% DUTY CYCLE RANGE
INTERNAL FEED-FORWARD LINE REGULA-
TION
INTERNAL CURRENT LIMITING
PRECISE 5.1V ± 2% ON CHIP REFERENCE
RESET AND POWER FAIL FUNCTIONS
SOFT START
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 500KHz
THERMAL SHUTDOWN
CONTINUOUS MODE OPERATION
DESCRIPTION
The L4975A is a stepdown monolithic power
switching regulator delivering 5A at a voltage vari-
able from 5.1 to 40V.
BLOCK DIAGRAM
MULTIPOWER BCD TECHNOLOGY
Multiwatt15V
ORDERING NUMBER: L4975A
Realized with BCD mixed technology, the device
uses a DMOS output transistor to obtain very high
efficiency and very fast switching times. Features
of the L4975A include reset and power fail for mi-
croprocessors, feed forward line regulation, soft
start, limiting current and thermal protection. The
device is mounted in a 15-lead multiwatt plastic
power package and requires few external compo-
nents. Efficient operation at switching frequencies
up to 500KHz allows reduction in the size and
cost of external filter components.
June 2000
1/21
This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice.