L4962/A STMicroelectronics

L4962 1.5A POWER SWITCHING REGULATOR 1.5A OUTPUT CURRENT 5.1V TO 40V OUTPUT VOLTAGE RANGE PRECISE ( 2%) ON-CHIP REFERENCE HIGH SWITCHING FREQUENCY VERY HIGH EFFICIENCY (UP TO 90%) POWERDIP HEPTAWATT VERY FEW EXTERNAL COMPONENTS (12 + 2 + 2) SOFT START ORDERING NUMBERS : L4962/A (12 + 2 + 2 Powerdip) INTERNAL LIMITING CURRENT L4962E/A (Heptawatt THERMAL SHUTDOWN Vertical) L4962EH/A (Horizontal Heptawatt) DESCRIPTION The L4962 is mounted in a 16-lead Powerdip plastic The L4962 is a monolithic power switching regula- tor delivering 1.5A at a voltage variable from 5V to package and Heptawatt package and requires very 40V in step down configuration. few external components. Features of the device include current limiting, soft Efficient operation at switching frequencies up to start, thermal protection and 0 to 100% duty cycle 150KHz allows a reduction in the size and cost of for continuous operating mode. external filter components. BLOCK DIAGRAM Pin X = Powerdip Pin (X) = Heptawatt June 2000 1/16L4962 ABSOLUTE MAXIMUM RATINGS Symbol Parameter Value Unit V Input voltage 50 V 7 V - V Input to output voltage difference 50 V 7 2 V2 Negative output DC voltage -1 V Output peak voltage at t = 0.1s f = 100KHz -5 V V , V Voltage at pin 11, 15 5.5 V 11 15 V Voltage at pin 10 7 V 10 I Pin 11 sink current 1 mA 11 I Pin 14 source current 20 mA 14 Power dissipation at T 90C (Powerdip) 4.3 W pins P tot T 90C (Heptawatt) 15 W case T, T Junction and storage temperature -40 to 150 C j stg PIN CONNECTION (Top view) THERMAL DATA Symbol Parameter Heptawatt Powerdip R Thermal resistance junction-case max 4 C/W - th j-case R Thermal resistance junction-pins max - 14C/W th j-pins R Thermal resistance junction-ambient max 50C/W 80C/W* th j-amb * Obtained with the GND pins soldered to printed circuit with minimized copper area. PIN FUNCTIONS FUNCTION HEPTAWATT POWERDIP NAME 1 7 SUPPLY VOLTAGE Unregulated voltage input. An internal regulator powers the internal logic. 2 10 FEEDBACK INPUT The feedback terminal of the regulation loop. The output is connected directly to this terminal for 5.1V operation it is connected via a divider for higher voltages. 3 11 FREQUENCY A series RC network connected between this terminal COMPENSATION and ground determines the regulation loop gain characteristics. 2/16