RDK-611

Reference Design Report for a 10 W Dual Title Output Power Supply Using TM InnoSwitch3 -EP INN3672C-H602 90 VAC 265 VAC Input Specification 5 V, 0.3 A and 12 V, 0.7 A Outputs Dual Output Open Frame Industrial Power Application Supply Author Applications Engineering Department Document RDR-611 Number Date May 02, 2018 Revision 1.2 Summary and Features InnoSwitch3-EP - industry first AC/DC ICs with isolated, safety rated integrated feedback Built in synchronous rectification for >85% efficiency at nominal AC input All the benefits of secondary side control with the simplicity of primary side regulation Insensitive to transformer variation Extremely fast transient response independent of load timing Meets output cross regulation requirements without linear regulators Primary sensed output overvoltage protection (OVP) eliminates optocoupler for fault protection Accurate thermal protection with hysteretic shutdown Input voltage monitor with accurate brown-in / brown-out and overvoltage protection 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 <RDR-611 10 W InnoSwitch3-EP Dual Output Supply 02-May-18 Table of Contents 1 Introduction ......................................................................................................... 4 2 Power Supply Specification ................................................................................... 6 3 Schematic ............................................................................................................ 7 4 Circuit Description ................................................................................................ 8 4.1 Input EMI Filtering ......................................................................................... 8 4.2 InnoSwitch3-EP Primary ................................................................................. 8 4.3 InnoSwitch3-EP IC Secondary ........................................................................ 8 5 PCB Layout ........................................................................................................ 10 6 Bill of Materials .................................................................................................. 11 7 Transformer (T1) Specification ............................................................................ 12 7.1 Electrical Diagram ........................................................................................ 12 7.2 Electrical Specifications ................................................................................ 12 7.3 Material List ................................................................................................ 12 7.6 Winding Illustrations .................................................................................... 14 8 Transformer Design Spreadsheet ........................................................................ 20 9 Performance Data .............................................................................................. 24 9.1 Full Load Efficiency vs. Line .......................................................................... 24 9.2 Efficiency vs. Load (0 A 0.7 A on 12 V, Full Load on 5 V) ............................. 25 9.3 Efficiency vs. Load (0 A 0.7 A on 12 V, No-Load on 5 V) .............................. 26 9.4 No-Load Input Power ................................................................................... 27 9.5 5 V Output Power with Low Input Power (No-Load on 12 V) .......................... 28 9.6 Line and Load Regulation ............................................................................. 29 9.6.1 Line Regulation (Full load) ..................................................................... 29 9.6.2 Cross Load Regulation ........................................................................... 30 10 Thermal Performance ...................................................................................... 34 10.1 90 VAC........................................................................................................ 34 10.2 265 VAC ...................................................................................................... 35 11 Over Temperature Protection (OTP) ................................................................. 36 11.1 90 VAC........................................................................................................ 36 11.2 265 VAC ...................................................................................................... 37 12 Waveforms ..................................................................................................... 38 12.1 Load Transient Response ............................................................................. 38 12.1.1 12 V Load Transient No-Load at 5 V Output ......................................... 38 12.1.2 5 V Load Transient No-Load at 12 V Output ......................................... 38 12.2 Switching Waveforms ................................................................................... 39 12.2.1 InnoSwitch3-EP Waveforms ................................................................... 39 12.2.2 InnoSwitch3-EP Drain Voltage and Current Waveforms During Start-up .... 39 12.2.3 SR FET Waveforms ............................................................................... 40 12.2.4 Output Voltage and Current Waveforms During Start-Up ......................... 41 12.2.5 Output Voltage and Current Waveform with Shorted Output (12 V).......... 42 12.2.6 Overvoltage Protection .......................................................................... 43 12.3 Output Ripple Measurements ........................................................................ 44 Power Integrations, Inc. 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