DER-237 CISPR22B EN55022B IEC950 UL1950 TYD2GM100G13O ECJ-3FB2J102K 440LD15-R

Title High Efficiency 18 W Power Supply Using TOPSwitch®-JX TOP264VG Specification 90 VAC 265 VAC Input; 12 V, 1.5 A

Design Example Report Title High Efficiency 18 W Power Supply Using TOPSwitch®-JX TOP264VG Specification 90 VAC 265 VAC Input; 12 V, 1.5 A Output Application Adapter Author Applications Engineering Department Document Number DER-237 DER-237 Date February 9, 2010 Revision 1.4 Summary and Features Low component count Small PCB size of 35 mm x 50 mm 132 kHz switching frequency reduces size of magnetics Very low no-load input power (85%) Exceeds Energy Star 2.0 Efficiency Requirements: >84% at 115 V / 60 Hz, and 230 V / 50 Hz, with very high efficiency in both standby and sleep modes Exceeds USA Energy Independence and Security Act 2007 of 76% Exceeds EU CoC v4 and EuP Tier 2 requirement of 80% Excellent transient load response Hysteretic thermal overload and over-voltage protection with automatic recovery Meets limited power source requirements ( -6dB QP margin PATENT INFORMATION The products and applications illustrated herein (including transformer construction and circuits external to the products) may be covered by one or more U.S. and foreign patents, or potentially by pending U.S. and foreign patent applications assigned to Power Integrations. A complete list of Power Integrations' patents may be found at www.powerint.com. Power Integrations grants its customers a license under certain patent rights as set forth at . Power Integrations 5245 Hellyer Avenue, San Jose, CA 95138 USA. Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com DER-237 DER-237 18 W / 12 V Adapter 09-Feb-10 Table of Contents 1 2 3 4 Introduction.4 Power Supply Specification .6 Schematic.7 Circuit Description .8 4.1 Input EMI Filtering .8 4.2 TOPSwitch-JX Primary.8 4.3 Energy Efficiency.9 4.4 Output Overvoltage Protection .9 4.5 Output Power Limiting .9 4.6 Output Rectification and Filtering .9 4.7 Thermal Overload Protection.9 5 PCB Layout .10 6 Bill of Materials .11 7 Transformer Specification.12 7.1 Electrical Diagram .12 7.2 Electrical Specifications.12 7.3 Materials.12 7.4 Transformer Build Diagram .13 7.5 Transformer Construction.14 8 Common Mode Coke Specification (L1) .15 8.1 Electrical Specifications.15 8.2 Materials.15 8.3 Winding instructions .15 8.4 Illustrations .15 9 Transformer Design Spreadsheet.16 10 Mechanical Drawings .21 10.1 TOP264VG (U1) Heatsink .21 10.2 Output Diode (D8) Heatsink .22 11 Performance Data.23 11.1 Full Load Efficiency .23 11.2 Active Mode Efficiency .24 11.3 Energy Efficiency Requirements .25 11.3.1 USA Energy Independence and Security Act 2007 .26 11.3.2 ENERGY STAR EPS Version 2.0 .26 11.4 No-load Input Power.27 11.5 Available Standby Output Power.28 11.6 Regulation .29 11.6.1 Load .29 11.6.2 Line .30 12 Thermal Performance .31 13 Waveforms.33 13.1 Drain Voltage and Current, Normal Operation.33 13.2 Output Voltage Start-up Profile.33 13.3 Drain Voltage and Current Start-up Profile .34 Power Integrations, Inc. Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 2 of 46 09-Feb-10 DER-237 DER-237 18 W, 12 V Adapter 13.4 Output Diode Peak Inverse Voltage.34 13.5 Load Transient Response (75% to 100% Load Step).35 13.6 Output Ripple Measurements .36 13.6.1 Ripple Measurement Technique.36 13.6.2 Measurement Results.37 13.7 Over-voltage Protection .38 13.8 Limited Power Source (Over Power Protection) .38 13.9 Control Loop Measurements .39 13.10 115 VAC Maximum Load .39 13.11 230 VAC Maximum Load .40 14 Conducted EMI .41 15 Revision History .45 Important Note: Although this board is designed to satisfy safety isolation requirements, the engineering prototype has not been agency approved. Therefore, all testing should be performed using an isolation transformer to provide the AC input to the prototype board. Page 3 of 46 Power Integrations Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com DER-237 DER-237 18 W / 12 V Adapter 09-Feb-10 1 Introduction This document is an engineering report describing an adapter power supply utilizing a TOPSwitch-JX TOP264VG. This power supply is intended as a general purpose evaluation platform for adapter application that operates from universal input and provides a 12 V, continuous 18 W output. PCB board dimension is 35 mm x 50 mm. The TOPSwitch-JX, by design, maintains virtually constant efficiency across a very wide load range without using special operating modes to meet specific load thresholds. This optimizes performance for existing and emerging energy-efficiency regulations. Maintaining constant efficiency ensures design optimization for future energy-efficiency regulation changes without the need for redesign. The low MOSFET capacitance of TOPSwitch-JX allows a higher switching frequency without the efficiency penalty which occurs with standard discrete MOSFET. The 132 kHz switching frequency (rather than the 40 kHz to 60 kHz frequency used for a discrete MOSFET) reduces the transformer size required, and so reduces cost. The power supply meets Energy Star 2.0 >79% average-efficiency, no-load