L4972AD

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 variable 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 microprocessors, 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 frequencies up to 200KHz allows reduction in the size and cost of external filter component. May 2005 Rev. 3 1/22 L4972A Table 2. Pin Description N° 1 2 3 4 5, 6 15, 16 7 8 9 10 11 12, 19 13 14 17 18 20 Pin BOOTSTRAP RESET DELAY RESET OUT RESET INPUT GROUND Fun...