Overview

The XL4005 (specifically XL4005E1 in a 5-lead TO-263 package) is a high-current 5.0 A5.0\text{ A} step-down (buck) DC-DC switching regulator manufactured by XLSEMI. Integrating a high-side N-channel power MOSFET switch, it operates over an input voltage range of 5.0 V5.0\text{ V} to 32.0 V32.0\text{ V} and regulates output voltage down to 0.8 V0.8\text{ V}.

Operating at a fixed switching frequency of 300 kHz300\text{ kHz}, the XL4005 achieves high power conversion efficiency (up to 95%95\%) while minimizing external inductor size compared to legacy 150kHz buck switchers.

Quick reference

Regulator TypeMonolithic High-Current Step-Down (Buck) Regulator
PackageTO-263-5L (D2PAK 5-Lead) / 5A Buck Module
Input Voltage Range (VINV_{IN})5.0 V5.0\text{ V} to 32.0 V32.0\text{ V} DC
Output Voltage Range (VOUTV_{OUT})0.8 V0.8\text{ V} to 30.0 V30.0\text{ V} DC (Adjustable)
Continuous Output Current (IOUTI_{OUT})Up to 5.0 A5.0\text{ A} (with adequate heatsinking)
Switching Frequency300 kHz300\text{ kHz} fixed internal clock
Conversion Efficiency90%…95%90\% \dots 95\%
Protection FeaturesThermal shutdown, short-circuit current limit, internal soft-start

Pinout (TO-263-5L Package)

text
        ┌──────────────────┐
        │     XL4005E1     │  (Front Package Face)
        └─┬───┬───┬───┬────┘
          1   2   3   4   5
         GND FB  VC  VIN SW
PinNameDescription
1GNDGround reference (0 V)
2FBVoltage feedback sense pin (0.8V0.8\text{V} internal reference voltage)
3VC / COMPError amplifier compensation pin for control loop frequency stabilization
4VINUnregulated DC power supply input pin (+5.0V to +32V DC)
5OUTPUT / SWSwitch node output connecting internal MOSFET to Schottky diode & inductor

Specifications

ParameterSymbolMinTypMaxUnitConditions
Input Voltage RangeVINV_{IN}5.012 / 2432VDC input operational range
Feedback Reference VoltageVFBV_{FB}0.7840.8000.816VVIN=12V,IOUT=0.5AV_{IN} = 12\text{V}, I_{OUT} = 0.5\text{A}
Continuous Output CurrentIOUTI_{OUT}—5.0—AVIN−VOUT≥2.0VV_{IN} - V_{OUT} \ge 2.0\text{V}
Current Limit ThresholdICLI_{CL}6.07.0—AInternal switch peak current limit
Switching FrequencyfSWf_{SW}240300360kHzInternal oscillator frequency
Quiescent CurrentIQI_Q—3.05.0mAOperating state (VFB=1.0VV_{FB} = 1.0\text{V})

Typical Application Circuit

text
       +V_IN (5.0V - 32V DC Input)
          │
       [Pin 4: VIN]
        XL4005E1 ──── [Pin 5: SW] ──── [ 33µH - 47µH Inductor ] ───┬─── +V_OUT Regulated DC Output
          │                                  │                     │
       [Pin 1: GND]               [B540 / SS54 Schottky Diode]  [ R1 ]
          │                                  │                     │
         GND ────────────────────────────────┴─────────────────────┼─── [Pin 2: FB]
                                                                   │
                                                                 [ R2 ]
                                                                   │
                                                                  GND

VOUT=0.8V×(1+R1R2)V_{OUT} = 0.8\text{V} \times \left( 1 + \frac{R_1}{R_2} \right)

Common mistakes

  • Exceeding the 32V input limit: The XL4005 maximum input rating is 32 V32\text{ V}. Operating near or above 32V (such as raw 24V AC transformer rectifications without clamping) can destroy the internal switch.
  • Using thin PCB traces for 5A current paths: Drawing 5A continuous requires wide copper traces or copper pours on VIN, SW, GND, and VOUT lines to prevent resistive voltage drops and thermal buildup.

Notes

  • XL4005 vs XL4015: XL4005 operates at 300 kHz300\text{ kHz} with a 0.8V0.8\text{V} feedback reference; XL4015 operates at 180 kHz180\text{ kHz} with a 1.25V1.25\text{V} feedback reference.

Assets & downloads