300W 20A DC-DC Buck Converter CC CV Step Down Module LED Driver

300W 20A high power buck converter with CC/CV module. Input 6-40V, output adjustable 1.2-36V, peak 20A. Up to 96% efficiency, dual heatsinks, short circuit protection. For high-power LED drivers, Li-Ion charging, industrial power, DIY adjustable supply

300W 20A DC-DC Buck Converter Module Application Features

Electrical Specifications

◆ Input Voltage
DC 6V ~ 40V (10V-40V recommended)

◆ Output Voltage
DC 1.2V ~ 36V (continuously adjustable)

◆ Output Current
Max 20A / 15A recommended for continuous use

◆ Output Power
Max 300W

◆ Conversion Efficiency
Up to 96% (24V to 12V @ 20A)

◆ Switching Frequency
150kHz ~ 200kHz

◆ Ripple Voltage
≤50mV

Operating Modes

◆ Constant Voltage (CV) Mode
Output voltage remains stable; ideal for general power supply applications

◆ Constant Current (CC) Mode
Output current remains stable; ideal for LED driving and battery charging

◆ Mode Indication
Red LED lights up when in constant current regulation

300W 20A DC-DC Buck Converter Module Adjustment Controls

◆ CV Potentiometer
Adjusts output voltage (clockwise to increase)

◆ CC Potentiometer
Adjusts output current / current limit (clockwise to increase)

◆ EN Pin
Enable control (Low = shutdown, High/Open = enable)

300W 20A DC-DC Buck Converter Module Protection Features

◆ Short Circuit Protection
Self-recovery (automatically resets after fault removal)

◆ Overcurrent Protection
Limits output current to safe levels

◆ Overtemperature Protection
Dual heatsinks for thermal management

◆ Input Reverse Polarity
No built-in protection (requires external diode)

300W 20A DC-DC Buck Converter Module Hardware Design

◆ Power Stage
75V/80A high-current dual MOSFET

◆ Capacitors
High-frequency low-resistance electrolytic capacitors for low ripple

◆ Heat Dissipation
2 aluminum heatsinks included

◆ Terminals
30A screw terminals for secure high-current connections

300W 20A DC-DC Buck Converter Module Physical Specifications

◆ Dimensions
Approx. 60×53×27mm

◆ Weight
Approx. 80-100g

◆ Mounting
Screw holes for secure installation

300W 20A DC-DC Buck Converter Module Applications

◆ LED Lighting

• High-power LED arrays

• LED display screens

• Stage/theater lighting

• Street lights and industrial lighting

◆ Battery Charging

• Lithium battery pack charging

• Lead-acid battery charging

• DIY power banks

◆ Industrial Equipment

• Motor speed control

• Industrial automation power supplies

• CNC machine power

◆ DIY Power Supply

• Adjustable bench power supply

• Solar power regulation

• Portable device power

300W 20A DC-DC Buck Converter Module Key Advantages

◆ High Power Handling
300W/20A capacity for demanding applications

◆ CC/CV Dual Mode
Versatile for both constant voltage and constant current applications

◆ High Efficiency
96% efficiency means less heat and energy savings

◆ Wide Input Range
6V-40V input works with various power sources

◆ Easy to Use
Screw terminals, onboard potentiometers, simple wiring

◆ Built-in Protection
Short circuit self-recovery, thermal management

◆ Cost-Effective
High performance at affordable price

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Notes : Since the prices of the electronic components are unstable, the prices we show are for reference only. Please confirm the recent prices with us before ordering!

Lead Time : Usually, your parcel will be arranged within 7 days after finishing payment. We'll send it more quickly if it's an urgent order. Thanks for your understanding!

Quantity(Pieces)	1 ~ 30000	30001 ~ 300000	> 300000
Est. Time(days)	5	7	To be negotiated

FAQ:

1. What is this 300W 20A DC‑DC buck converter module and its key specifications?
   This is a high‑power step‑down (buck) converter that combines constant voltage (CV) and constant current (CC) regulation in a single module. It can deliver up to 20 A of output current and handle up to 300 W of power, making it ideal for driving high‑power LEDs, charging large battery packs, and serving as an adjustable bench power supply. Key specifications: input voltage 6 V – 40 V DC, adjustable output 1.2 V – 36 V (must be lower than the input), maximum continuous output current 20 A (with adequate cooling), typical conversion efficiency up to ~95 %, switching frequency around 150 kHz – 300 kHz, and built‑in over‑current, over‑temperature, and reverse‑input‑polarity protection (on many models). The board includes multi‑turn potentiometers for precise CV and CC adjustment, LED indicators for operating mode, and large screw terminals for high‑current wiring.

2. How does the CC/CV (constant current / constant voltage) mode work?
   The module has two adjustment knobs: one for output voltage (CV) and one for output current limit (CC). In CV mode, the output voltage stays fixed at your set value, and the current varies with the load — this is the normal power‑supply mode. In CC mode, the module automatically reduces the output voltage to ensure the current never exceeds the set limit. This is essential for driving LEDs (which must be current‑driven) and for charging lithium batteries (the battery starts at low voltage, draws constant current until the voltage reaches the CV setpoint, then current tapers off). The on‑board LED indicator typically shows red in CC mode and green in CV mode.

3. How do I adjust the output voltage and current limit?
   Before connecting any load, power the module and use a small screwdriver. To set the voltage: turn the CV potentiometer clockwise to increase the voltage and counter‑clockwise to decrease, monitoring the output with a multimeter. To set the current limit: temporarily short the output terminals through a multimeter in 10 A or 20 A current mode, then turn the CC potentiometer to set the desired maximum current. Never adjust the current limit with a load connected — this can send excessive current to the load. After setting, remove the short and connect your load. The multi‑turn pots allow very fine adjustment.

4. What is the maximum input voltage and output current? Does it need a heatsink?
   The maximum rated input voltage is 40 V DC. The module can deliver up to 20 A of continuous output current, but this is only achievable with excellent cooling. At power levels above 100 W – 150 W, the module will become very hot. It is strongly recommended to attach a large aluminium heatsink to the power devices and ensure forced‑air cooling (a fan) for sustained operation above 10 A. The built‑in over‑temperature protection will reduce output or shut down the module if it overheats. For reliable long‑term use, keep the total output power below approximately 250 W unless excellent ventilation is provided.

5. What is the typical efficiency of this buck converter?
   This module uses a synchronous or quasi‑synchronous buck topology and can achieve a peak efficiency of up to 95 % under optimal conditions (moderate load, moderate input‑output voltage difference). Efficiency drops slightly at very light loads or when the step‑down ratio is very large (e.g., 40 V to 5 V). At full 20 A load, even with 90 % efficiency, several tens of watts are dissipated as heat, which is why a fan and heatsink are essential for high‑power operation.

6. What protection features does this module include?
   The module provides several built‑in protections: over‑current protection (CC mode), over‑temperature protection (thermal shutdown or power reduction), short‑circuit protection (the current limit automatically prevents damage), and on some models reverse‑input‑polarity protection (via a diode or MOSFET). However, it is still good practice to double‑check the input polarity. There is no output over‑voltage protection — if the feedback loop fails, the output can rise to the input voltage, so always set the voltage before connecting sensitive loads.

7. How do I use this module as an LED driver?
   High‑power LEDs must be driven with constant current, not constant voltage. First, calculate the total forward voltage of your LED string. Set the CV potentiometer to a voltage 1 V – 2 V higher than the LED string's total forward voltage (but not exceeding 36 V). Then set the CC potentiometer to the LED's rated current (e.g., 3 A, 5 A, or 10 A). Connect the LED string directly to the output — the module will automatically operate in CC mode, limiting the current to your set value. Never connect LEDs without first setting the current limit, or they will be destroyed by over‑current.

8. Can this module charge lithium batteries? How do I configure it?
   Yes, the CC/CV characteristic makes it an excellent multi‑cell lithium battery charger. Set the CV (output voltage) to the battery pack's full charge voltage: 4.2 V per cell (e.g., 12.6 V for a 3S pack, 16.8 V for 4S). Set the CC (current limit) to the desired charge current (typically 0.5C to 1C of the battery capacity). Connect the battery with correct polarity. The module will charge in CC mode first (red LED), then automatically switch to CV mode (green LED) when the battery reaches the set voltage. The module does not terminate charging — you must disconnect the battery once the current drops to near zero to prevent over‑charging.

9. How does this module compare to smaller buck converters like the XL4015 or XL4016?
   The main difference is output current capability. The XL4015 is limited to 5 A, and the XL4016 to about 8 A. This 300 W module can deliver up to 20 A, making it suitable for driving large LED arrays, charging high‑capacity batteries quickly, or powering heavy loads that smaller modules cannot handle. It also uses multiple parallel MOSFETs and a larger inductor to manage the higher current, and it requires much more substantial cooling. For most low‑power (under 5 A) projects, the XL4015 is more compact and easier to use; for high‑current applications, this module is the right choice.

10. Why does my module get extremely hot or shut down at high current? How can I fix it?
    High current generates significant heat. If the module shuts down, it is likely the over‑temperature protection kicking in. Solutions: 1) attach a large heatsink to the power MOSFETs and diode; 2) add a fan blowing directly onto the module; 3) reduce the input‑output voltage difference (the larger the drop, the more heat); 4) improve airflow around the module; 5) check that the input power supply is stable and can deliver the required current. Also, ensure the screw terminals are tight — loose connections cause resistance and additional heat.