70W 适配器设计实例.pdf

Engineering Prototype Report - Title 70 W (19 V 3.66A) Universal Input Adapter (EP11) Target Laptop Adapters, LCD Monitors, Applications Audio, High Power Adapters Author Power Integrations Applications Dept. Doc Num EPR-00011 Date 22-January-2001 Revision 1.4 Features • Very compact design: (4.1” × 2.25” × 1.06”) • High power density - 7 W / inch³ • Full output power (70 W) in sealed enclosure at 40°C ambient • High efficiency: 84% (85 VAC ), 89% (230 VAC ) • Low no-load consumption: 350 mW (115 VAC ), 500 mW (230 VAC ) • Low value input capacitor: 74% DCMAX and line feed forward allows 2 µF/W • Power limited during overload: overload output current less than 5 A at 19 V • Primary side soft-start: minimizes component stresses during start-up • Low EMI due to frequency jittering: meets CISPR22B with output cap. earthed • Line under voltage sense: no output glitches on power up or power down • Line over voltage shutdown: extended line surge protection • Hysteretic thermal shutdown: supply automatically recovers when fault is removed • Low component count: simple circuit and design • Single sided PC board: no plated through holes • No surface mount components required Power Integrations Inc 5245 Hellyer Avenue, San Jose, CA 95138 USA. Tel: +1 408 414 9200 Fax: +1 408 414 9201 www: EPR-00011 - 70 W Adapter 22-Jan-01 Table of Contents 1 Introduction4 2 Power Supply Specification 6 3 Schematic7 3.1 Description7 4 PCB Layout10 5 Bill of M