Circuit design of VAC multi-output set-top box power supply

September 10, 2022

Summary:

Way of working

The figure design uses TOP247YN and applies many features of TOPSwi tch-GX. Line voltages UV and OV (100 V and 450 V each) are implemented with a 2 MΩ resistor (R1). Undervoltage eliminates output jitter on/off, and overvoltage provides protection against input voltage transients and prolonged surges. R4 sets U1's internal current limit to 80% of the nominal value, limiting the overload power.

design feature

  • Low cost, low component count
  • Excellent output voltage tracking and cross regulation - no linear regulator required
  • High efficiency, efficiency >71% at 90 VAC input
  • Line Voltage Undervoltage Detection (UV) and Power System Surge Protection (OV)
  • Meets CISPR22B/EN55022B conducted EMI limits
  • Pass 4 kV differential mode and common mode surge test (EN61000-4-5)
  • Pass 4 kV/100 kHz ringing wave test (IEEE C62.41)

See the PDF document for details (click on the PDF file to download)

72V BMS

HuiZhou Superpower Technology Co.,Ltd. , https://www.spchargers.com

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