300W 20A DC-DC Buck Converter

The 300W 20A DC-DC Buck Converter is a highly efficient, constant-voltage / constant-current (CV/CC) step-down power module. It is designed to take a higher DC input voltage and accurately reduce it to a stable, lower DC output voltage.

Core Technical Specifications

• Input Voltage Range: 6V to 40V DC (10V to 40V is highly recommended for stability).
• Output Voltage Range: 1.2V to 36V DC (fully adjustable via potentiometer; input must be greater than output).
• Output Current: Up to 20A maximum (15A is recommended for continuous long-term operation).
• Maximum Output Power: 300W.
• Conversion Efficiency: Typically 95% to 97% (measured when converting 24V down to 12V at 20A).
• Output Ripple: ≤50mV.
• Key Components: Designed with a high-current 75V / 80A dual MOS tube and high-frequency, low-resistance electrolytic capacitors to maintain ultra-stable output.

On-Board Layout & Pin Configuration

The module features screw terminal blocks for secure connections and two multi-turn trimmers (potentiometers):

• +IN / -IN: Connect your DC input source (e.g., 24V power supply or battery).
• VO+ / VO-: Connect your target device or load.
• CV Trimmer (Nearest to Voltage Input): Turn clockwise to increase and counter-clockwise to decrease the output voltage.
• CC Trimmer (Nearest to Voltage Output): Turn clockwise to increase and counter-clockwise to decrease the current threshold.

Important Usage Tips & Safety Notes

• Thermal Management: The module includes built-in dual heat sinks. However, if your continuous load exceeds 15A or 50W, or if the ambient temperature is above 40°C, you must add an external cooling fan to prevent thermal damage.
• Setting Current Limits: Unlike lower-power modules (like the XL4015), you cannot safely short-circuit the output terminals of this module to preset the current limit. You must connect a load first (or use a high-capacity discharge battery/electronic load) and monitor it with a multimeter while adjusting the CC trimmer.
• Potentiometer Troubleshooting: If you turn the voltage knob and the output voltage stays exactly equal to your input voltage, the potentiometer is at its upper limit. Rotate the CV trimmer counter-clockwise for 15 to 20 full turns until the voltage begins to drop and regulate properly.