0-35V Variable Power Supply Using XL4015 DC-DC Converter

DIY Variable Power Supply Using XL4015:

In this post we will design a Variable Power Supply Using XL4015 DC-DC Buck Converter Module. The Variable output voltage is 1.25 Volt to 35 Volt and the Current ranges from 0-5 Ampere. We can also design power supply using LM317T adjustable power supply IC but the output sometimes gets fluctuates and isn’t stable. But XL4015 output is very accurate and the output is stable. The best part about is that there is no need for PCB designing neither you need any electronic components as it already comes with a module.

Components Required:

1. 5A XL4015 DC-DC Adjustable Step-Down Power Module
2. 230V to 30V step down transformer
3. Fuse 5A
4. 4 1N4001 Diode
5. 470uF Electrolytic Capacitor
6. 0.1uF Capacitor

XL4015 DC-DC Adjustable Step-Down Power Module:

The XL4015 is a 180 kHz fixed frequency PWM buck (step-down) DC to DC converter, capable of driving a 5 Ampere load with high efficiency, low ripple, and excellent line and load regulation. Requiring a minimum number of external components, the regulator is simple to use and include internal frequency compensation and a fixed-frequency oscillator. The PWM control circuit is able to adjust the duty ratio linearly from 0 to 100%. An overcurrent protection function is built inside. When short protection function happens, the operation frequency will be reduced from 180KHz to 48KHz. An internal compensation block is built in to minimize external component count.

Specifications:

1. Module Properties: Non-isolated step-down module (BUCK)
2. Input voltage: 4-38V (input please try not to exceed 38V)
3. Output voltage: 1.25-36V continuously adjustable
4. Output Current: 0-5A
5. Output Power: 75W
6. Operating temperature: -40 to +85 degrees
7. Operating frequency: 180 kHz
8. Conversion efficiency: up to 96%
9. Load regulation: S (the I) ≤0.8% (input 24V, output 12V, load change from 1 ~ 4.5A measured)
10. Voltage Regulation: S (U) ≤0.8% (output 12V, when 4A, voltage changes from 18 ~ 32V measured)
11. Power Indicator: Yes
12. Short circuit protection: Yes (limited current 8A)
13. Over-temperature protection: Yes (automatic shut off the output after overtemperature)
14. Connection: Welding, V-IN is the input, V-OUT output

Applications:

1. It can be used for step-down voltage with input higher the output voltage, such as batteries, power transformers.
2. DIY adjustable power supply
3. Industrial equipment buck 12V to 3.3V, 12V to 5V, 24V to 5V, 24V to 12V, 36V 24V to and so on.
4. LCD Monitor and LCD TV
5. Portable instrument power supply
6. Telecom / Networking Equipment

0-35V Variable Power Supply Circuit Using XL4015:

The module can take a power up to 38V as input but we have used 30V input. For this, we need 230V to 30V step-down transformer. The output of the transformer is given to the input of the Rectifier Diode as shown in the figure above. The output of the diode is then directly supplied to the input of the XL4015 Module. But before that, we have used two Capacitors which are used for waveform smoothing or removing any ripples or unnecessary signals. Now the final output can be taken from the output of the XL4015 Module.

Thus this is the simple DIY Variable Power Supply Circuit that can easily be designed at home and used for multiple applications.

Video Tutorial & Explanation: