XL4015 5A buck converter: specs and pinout
A step-down (buck) converter module built around the XL4015 regulator chip, which is a 180 kHz fixed-frequency buck converter rated for a 5 A load and an output adjustable between 1.25 V and 32 V. The facts below are the chip's. The module board itself is not covered by an official document.
Specs
| Spec | Value | Source |
|---|---|---|
| Input voltage (chip) | 8 V to 36 V operating; absolute maximum 40 V | source Features p.1; DC parameters p.5; Absolute Maximum Ratings p.4 |
| Output voltage (chip) | Adjustable from 1.25 V to 32 V; feedback reference 1.25 V (1.225 V to 1.275 V); VOUT = 1.25 x (1 + R2/R1) | source Features p.1; Electrical Characteristics p.5; Typical Application p.3 |
| Output current (chip) | 5 A constant output current capability | source Features p.1 |
| Switching frequency | 180 kHz (144 kHz to 216 kHz); drops to 48 kHz during output short | source Electrical Characteristics, DC parameters p.5 |
| Efficiency (sheet test circuit) | 87 % at 12 V in, 5 V out, 5 A; 93 % at 24 V in, 12 V out, 4 A | source Electrical Characteristics p.5 |
| Switch current limit | 7 A typical | source Electrical Characteristics, DC parameters p.5 |
| Quiescent current | 2.1 mA typical, 5 mA maximum | source Electrical Characteristics, DC parameters p.5 |
| Minimum dropout | 0.3 V | source Features p.1 |
| Thermal resistance, junction to ambient (TO263-5L, no heat sink, free air) | 30 C/W | source Absolute Maximum Ratings p.4 |
| Junction temperature | -40 C to 125 C | source Absolute Maximum Ratings p.4 |
Power
| Value | Source | |
|---|---|---|
| Supply | 8 V to 36 V at the chip's VIN pin | source Electrical Characteristics p.5 |
| Current | 2.1 mA quiescent (chip, typical) | source Electrical Characteristics p.5 |
Chip pins
These are the pins of the chip on the module, from the chip datasheet. The module's own header may label or expose them differently.
The pin rows are the XL4015 chip's TO263-5L pins. The module's terminals, trimmer, indicator and any current-limit circuit are not covered by an official document; read the module's own markings for input and output terminals.
| Pin | Function | Voltage | Notes | Source |
|---|---|---|---|---|
| 1 | GND | Ground pin; the sheet asks for care in layout. | source Pin Configurations / Table 1, p.2 | |
| 2 | FB | 1.25 V threshold | Feedback; an external resistor divider senses the output voltage. | source Pin Configurations / Table 1, p.2 |
| 3 | SW | Power switch output (the metal tab is also SW). | source Pin Configurations / Table 1, p.2 | |
| 4 | VC | Internal regulator bypass pin; connect a 1 uF capacitor to VIN. | source Pin Configurations / Table 1, p.2 | |
| 5 | VIN | 8 V to 36 V | Supply input; bypass to GND with a suitably large capacitor. | source Pin Configurations / Table 1, p.2 |
Build with it
Project ideas for the XL4015 5A buck converter. Each link opens Soldr with the prompt filled in; Soldr assigns the pins, checks power and shows how to wire every part.
- 12 V to 5 V rail for an ESP32 weather node: The chip takes 8 V to 36 V in and its output is adjustable, so a 12 V adapter is inside the range. Set the output to 5.0 V and check it with the multimeter before connecting the ESP32's 5 V input. The load here is far below the 5 A rating, so heat is small. The adapter ends in a barrel plug and no barrel-to-terminal lead is sold here: connect it to the module's input screw terminals with a barrel-jack-to-terminal adapter you already own, or with the supply's bare-wire output if it has one, wired + and - as the supply's label shows. Do not wire a bare mains supply.
- Adjustable test rail for 3.3 V and 5 V experiments: Output is set by a divider against a 1.25 V reference, so it can be dialled to the voltage you need; check it with the multimeter first, then connect the breadboard. Learning project. Keep the load well below the 12 V adapter's rating. The adapter ends in a barrel plug and no barrel-to-terminal lead is sold here: connect it to the module's input screw terminals with a barrel-jack-to-terminal adapter you already own, or with the supply's bare-wire output if it has one, wired + and - as the supply's label shows.
- Powering a NodeMCU and a small relay board from 12 V: The buck converter provides the 5 V rail from 12 V; set it with the multimeter before connecting. The relay's switched side is for low-voltage loads only. Wiring anything on mains must be done by a qualified person and is not part of this idea. The adapter ends in a barrel plug and no barrel-to-terminal lead is sold here: connect it to the module's input screw terminals with a barrel-jack-to-terminal adapter you already own, or with the supply's bare-wire output if it has one, wired + and - as the supply's label shows.
Common mistakes
- Feeding it less than 8 V or more than 36 V: the chip regulates from 8 V to 36 V and its absolute maximum is 40 V (source: link, p.4-5). The module's own capacitors and parts are not documented, so stay below the voltage printed on the module's input capacitors.
- Running 5 A without cooling: the sheet's own test circuit gives 87 % efficiency at 12 V to 5 V and 5 A, which means roughly 3.7 W is lost as heat at that point (25 W out / 0.87 = 28.7 W in; derived from the sheet's 87 %), and the sheet lists 30 C/W for the bare package in free air (source: link, p.4-5). Give it a heat sink and airflow for continuous high-current use.
- Connecting the load before setting the output: the output is set by a resistor divider against a 1.25 V reference, so measure the output with a meter before connecting a 3.3 V or 5 V board (source: link, p.3).
Not covered by the official source
- The module board is not covered by an official document: its terminals, trimmer, current-limit and indicator circuits, and its rated current are not stated here.
- The sheet gives no output ripple figure in the pages used.
Sources
- link (XLSEMI XL4015 datasheet, Rev 2.0; maker host)