PowerDC-DC ConvertersPartial

XL4015 Buck Converter Module

5A adjustable step-down power supply

MAYBE

Analysis of cheap XL4015-based buck converter modules. Can they actually deliver 5A, and are they safe for your projects?

November 15, 2024
v1.0.0

Verdict Rationale

Works well within derated specifications (3A continuous), but thermal management and component quality concerns limit full-power operation.

Specifications

Input Voltage4-38V DC
Output Voltage1.25-36V DC(Adjustable)
Max Current5A(Claimed, see analysis)
EfficiencyUp to 96%(At optimal load)
Switching Frequency180 kHz
Size54 x 23 x 15mm

Overview

The XL4015 buck converter module is ubiquitous on AliExpress, promising 5A output at prices under $2. Our testing reveals significant gaps between marketing claims and real-world performance.

Thermal Analysis

Thermal Warning

At 5A output, the XL4015 IC reaches 95°C within 5 minutes without additional heatsinking. This exceeds safe operating limits.

Temperature vs Load (25°C ambient, no heatsink)

Load CurrentIC TemperatureInductor Temp
1A45°C35°C
2A58°C48°C
3A72°C62°C
4A85°C75°C
5A95°C+85°C

Component Quality Issues

Teardown of 5 modules revealed:

  1. Capacitors: Marked as 100µF/50V, actual capacitance measured 60-80µF
  2. Inductor: Adequate for 3A, saturates at higher currents
  3. Diode: SS54 Schottky appears genuine
  4. IC: XL4015 marking consistent, likely authentic

Safe Operating Recommendations

For reliable operation:

max_continuous_current: 3A
recommended_with_heatsink: 4A
input_output_differential: ">3V for efficiency"
ambient_temperature: "<40°C"

Modifications for Better Performance

  1. Add heatsink: Aluminum plate or finned heatsink on IC
  2. Replace capacitors: Use quality 105°C rated electrolytics
  3. Improve airflow: Add small fan for >3A loads
  4. Add input capacitor: Extra 470µF for input stability

Use Cases

LED Driver

good

Powering LED strips at 2-3A

Bench Power Supply

good

Adjustable voltage for testing

5A Continuous Load

poor

Running at rated maximum

Battery Charging

fair

CC/CV charging applications

Risks & Considerations

safetyMedium

Thermal runaway possible at high loads without heatsinking

Mitigation: Add heatsink, limit to 3A continuous

qualityHigh

Capacitors often underrated or counterfeit

Mitigation: Replace electrolytic caps with quality units

reliabilityMedium

Potentiometer failure can cause voltage spikes

Mitigation: Use fixed resistors for critical applications