4.1 AC Input and EMI Filtering (mains)
By sensing zero current, the IC reduces switching losses in the boost diode, leading to higher overall efficiency. a20112 power supply schematic
AC Input → EMI Filter → Bridge Rectifier → Bulk Capacitor → Switching MOSFET → Flyback Transformer → Secondary Rectifier → Output Filter → DC Output ↑ ↓ PWM Controller ← Optocoupler ← Voltage Reference (TL431) ← Voltage Divider a20112 power supply schematic
If you are looking to purchase a replacement or find a specific technician-level schematic: a20112 power supply schematic