L4973D5.1

® L4973V3.3 - L4973V5.1 L4973D3.3 - L4973D5.1 3.5A STEP DOWN SWITCHING REGULATOR UPTO 3.5ASTEP DOWNCONVERTER OPERATING INPUT VOLTAGE FROM 8V TO 55V 3.3V AND 5.1V (±1%) FIXED OUTPUT, AND ADJUSTABLE OUTPUTS FROM: 0V TO 50V (3.3V type) 5.1V TO 50V (5.1 type) FREQUENCY ADJUSTABLE UP TO 300KHz VOLTAGE FEED FORWARD ZERO LOAD CURRENT OPERATION (min 1mA) INTERNAL CURRENT LIMITING (PULSE BY PULSE AND HICCUP MODE) PRECISE 5.1V (1.5%) REFERENCE VOLTAGE EXTERNALLY AVAILABLE INPUT/OUTPUT SYNCHRONIZATION FUNCTION INHIBIT FOR ZERO CURRENT CONSUMPTION (100µA Typ. at VCC = 24V) PROTECTION AGAINST FEEDBACK DISCONNECTION THERMAL SHUTDOWN OUTPUT OVERVOLTAGE PROTECTION SOFT START FUNCTION TYPICAL APPLICATION CIRCUIT (POWERDIP) MULTIPOWER BCD TECHNOLOGY POWERDIP (12+3+3) SO20(12+4+4) ORDERING NUMBERS: L4973V3.3 (Powerdip) L4973D3.3 (SO20) L4973V5.1 (Powerdip) L4973D5.1 (SO20) DESCRIPTION The L4973 is a step down monolithic power switching regulator delivering 3.5A at fixed voltages of 3.3V or 5.1V and using a simple external divider output adjustable voltage up to 50V. Realized in BCD mixed technology, the device VCC (8V to 55V) ROSC CIN C2 7 8 10 12 CBOOT VO(3.3V or 5.1V) L1 1 4,5,6, 13,14,15 16 L4973 17 9 3 11 2 RCOMP COSC CSS CCOMP D1 COUT D97IN554A April 2000 1/16 L4973V3.3 - L4973V5.1 - L4973D3.3 - L4973D5.1 uses an internal power D-MOS transistor (with a typical Rdson of 0.15ohm) to obtain very high efficiency and very fast switching times. Switching frequency up to 30...