SI34061ISOC4-KIT Silicon Labs

UG333: Class 4, 30 W EMI Compliant Isolated Evaluation Board for the Si34061 The Si34061 isolated Flyback evaluation board is a reference de- KEY FEATURES sign for power supplies in Power over Ethernet (PoE) Powered Device (PD) applications. IEEE 802.03at compatible High efficiency (> 90%) The Si34061-EVB-EXT-5V maximum output is Class 4 power (30 W with isolated 5 V EMI compliant design output). Synchronous rectification The Si34061 IC integrates an IEEE 802.03at compatible PoE+ interface as well as a High flexibility peak-current-control dc-dc controller. Integrated transient overvoltage protection Thermal shutdown protection 5x5 mm 24-pin QFN Parameter Condition Specifications Ordering part number Si34061FB5VC4-KIT Up to Pout = 25.5 W, Connector J1 42.5 to 57 V PSE input voltage range Up to Pout = 12.95 W, Connector J1 37 to 57 V Wall adapter input voltage range Connector J3 33 to 57 V PoE Type/Class Type 2/Class 4 IEEE 802.3at Output voltage/current Connectors J4-J5 5 V / 6 A Efficiency, end-to-end V = 48 V from wall adapter 89.7 % IN V = 50 V from PSE Efficiency, dc-dc converter 91.5 % IN V = 50 V from PSE Efficiency, end-to-end 89.1 % IN Switching frequency R (R14) = 95.3 k 200 kHz FREQ Conducted EMI EN55032, average and peak detector Passed Radiated EMI EN55032 Class B Passed silabs.com Building a more connected world. Rev. 0.5 Table of Contents 1. Kit Description and Powering up the Si34061-EVB-EXT-5V ..............3 2. Si34061-EVB-EXT-5V Board Schematics.....................4 3. Conversion Efficiency of the Si34061-EVB-EXT-5V Board...............6 4. SIFOS PoE Compatibility Test Results......................8 5. Feedback Loop Phase and Gain Measurement Results (Bode Plots) ..........9 6. Load Step Transient Measurement Results ................... 10 7. Output Voltage Ripple ........................... 11 8. Soft Start Protection ...........................12 9. Output Short Protection .......................... 13 10. Pulse Skipping at No-Load Condition..................... 14 11. Adjustable EVB Current Limit........................ 15 12. Tunable Switching Frequency .......................16 13. Synchronous Rectification......................... 17 14. Maintain Power Signature ......................... 18 15. Wall Adapter Support with Priority over PSE .................. 19 16. Radiated Emissions Measurement ResultsEN55032 Class B ........... 20 16.1 Radiated EMI Measurement Process......................20 17. Conducted Emissions Measurement ResultsEN55032 .............21 18. Thermal Measurements .......................... 22 19. Layout ................................ 23 20. Bill of Materials ............................. 25 21. Design and Layout Checklist ........................ 28 silabs.com Building a more connected world. Rev. 0.5 2