L4972A_05 Datasheet, PDF (1/22 Pages) STMicroelectronics – 2A SWITCHING REGULATOR

L4972A
2A SWITCHING REGULATOR
1 Features
■ 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
HYSTERETIC TURN-ON
■ PWM LATCH FOR SINGLE PULSE PER
PERIOD
■ VERY HIGH EFFICIENCY
■ SWITCHING FREQUENCY UP TO 200KHz
■ THERMAL SHUTDOWN
■ CONTINUOUS MODE OPERATION
2 Description
The L4972A is a stepdown monolithic power
switching regulator delivering 2A at a voltage vari-
able from 5.1 to 40V.
Realized with BCD mixed technology, the device
Figure 2. Block Diagram
Figure 1. Packages
PowerDIP20 (16+2+2)
Table 1. Order Codes
Part Number
L4972A
L4972AD
L4972AD013TR
SO20
Package
DIP20 (16+2+20)
SO20
SO20 in Tape & Reel
uses a DMOS output transistor to obtain very high
efficiency and very fast switching times. Features
of the L4972 include reset and power fail for micro-
processors, feed forward line regulation, soft start,
limiting current and thermal protection. The device
is mounted in a Powerdip 16 + 2 + 2 and SO20
large plastic packages and requires few external
components. Efficient operation at switching fre-
quencies up to 200KHz allows reduction in the
size and cost of external filter component.
May 2005
Rev. 3
1/22