L4964

L4964 HIGH CURRENT SWITCHING REGULATOR . . . . . . . . . . . . 4 A OUTPUT CURRENT 5.1 V TO 28 V OUTPUT VOLTAGE RANGE 0 TO 100 % DUTY CYCLE RANGE PRECISE (± 3 %) ON-CHIP REFERENCE SWITCHING FREQUENCY UP TO 120 KHz VERY HIGH EFFICIENCY (UP TO 90 %) VERY FEW EXTERNAL COMPONENTS SOFT START RESET OUTPUT CURRENT LIMITING INPUT FOR REMOTE INHIBIT AND SYNCHRONUS PWM THERMAL SHUTDOWN MUL TIW AT T15 Vertical (Plastic Package) ORDERING NUMBER : L4964 DESCRIPTION The L4964 is a stepdown power switching regulator delivering 4A at a voltage variable from 5.1V to 28V. Features of the device include overload protection, soft start, remote inhibit, thermal protection, a reset output for microprocessors and a PWM comparator input for synchronization in multichip configurations. The L4964 is mounted in a 15-lead Multiwatt® plastic power package and requires very few external components. Efficient operation at switching frequencies up to 120kHz allows a reductionin the size and cost of external filter components. PIN CONNECTION (top view) MULTIWATT15 Horizo ntal (Plastic Package) ORDERING NUMBER : L4964HT Pins 1, 4, 15 must not be connected. Leave open circuit. April 1993 1/13 L4964 PIN FUNCTIONS N° 1 2 3 4 5 Name N.C. Output Supply Voltage N.C. Soft Start Regulator Output. Unregulated Voltage Input. An internal regulator powers the L4964’s internal logic. Must not be connected. Leave open circuit. Soft Start Time Constant. A capacitor is connected between this terminal and ground to de...