Wannien 101v0 Power Supply Schematic Verified

Look for "domed" or leaking electrolytic capacitors. These are the #1 cause of failure in SMPS boards.

Incorrect schematics show a 1.5M or 2M resistor from bulk capacitor to IC pin 8. 4.7M Ohms (Yellow, Purple, Green, Gold). Why it matters: Using a 2M resistor will overheat the LD7750R at 240VAC. Using a 10M will fail to start below 100VAC.

The IC steps down the 12-15V input to a highly precise, regulated 5V output rail . This rail supplies power directly to microcontrollers, logic gates, or display scaling modules down the line.

Reset/brown-out and supervision

Dual or single-rail configurations (commonly 12V DC and 5V DC rails) Cooling: Natural convection (passive cooling) 2. Verified Schematic Topology Breakdown

If you must unsolder and replace the primary switching MOSFET, clean the heatsink completely and apply fresh, high-quality thermal paste or replace the silicone insulating pad to maximize heat dissipation.

: Large yellow/blue coil that outputs high voltage to the CCFL connectors. 🛠️ Common Repair Data Component Label Common Value/Part Number 2A / 250V Slow-Blow Main Input Protection 470uF - 1000uF / 25V Secondary 12V Filtering (Fail often) 1000uF / 10V Secondary 5V Filtering (Fail often) 2SK2645 or 7N60 Primary Switching MOSFET LD7552 or LD7575 Power PWM Controller 🔍 Troubleshooting Steps Dead Board wannien 101v0 power supply schematic verified

Rectify the high-frequency AC output into DC. Schottky diodes are used because they handle high speeds and have a low forward voltage drop.

If the power supply is healthy, the bulb will flash briefly (as the bulk cap charges) and then go dim or stay unlit. Step 4: Voltage Verification

the exact feedback loop parameters to ensure rock-solid voltage stability. Look for "domed" or leaking electrolytic capacitors

Actuates output rails OUT1–OUT4 based on logic trigger voltages. Main Filter Capacitors

your local AC line voltage across the large primary capacitor.