S36012 Power Supply Circuit Diagram

AC Input (L,N) --> EMI Filter --> Bridge Rectifier --> Bulk Capacitors --> MOSFETs
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                                                                   [PWM IC KA7500C]
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Main Transformer --> Schottky Diodes --> LC Filter --> DC Output (+12V)
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      Aux Winding --> Vcc for PWM IC                    |
                                                    Feedback Divider
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                                              Optocoupler <-- TL431

Using the schematic, you can troubleshoot known issues:

| Symptom | Suspect Component (Per Diagram) | Diagnostic Test | | :--- | :--- | :--- | | Dead unit, no output | Fuse, NTC thermistor, Bridge diodes (D1-D4) | Check continuity; check for shorted bulk capacitors (C5, C6). | | Output voltage oscillates / clicks | Startup resistor (R3, 150k 2W) or TL494 VCC capacitor (C22, 47µF) | Measure voltage on TL494 pin 12 (should be stable 12-20V). | | Low voltage (e.g., 8V) under load | Output filter capacitors (C19, C20) bulging; Shorted Schottky diode (D14, D15) | ESR meter on caps; diode check mode on DMM for shorts. | | Blows fuse immediately | Shorted switching transistors (Q1 or Q2); Shorted bridge rectifier | Transistor tester: check B-C-E for shorts. | | High ripple noise | Output choke (L1) loose; Capacitors C19/C20 dried out | Oscilloscope; substitute with known good caps. | s36012 power supply circuit diagram

Do not exceed the MOSFET’s Vds rating. With an IRFB4110 (100V), you can raise input to 50V. However, you must: AC Input (L,N) --> EMI Filter --> Bridge

Many online copies of the S36012 power supply circuit diagram are blurry or missing component values. Here are three tips to interpret them: Using the schematic, you can troubleshoot known issues: