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The HL5501 is high voltage protection load switch to protect system against positive and negative COIL pin voltage faults up to ±40V, and features low switch ON resistance, 90mΩ (typ). The device features two internal MOSFETs connected in series, therefore two power pins, COIL and AC, are completely isolated when it is disabled.

HL5501 employs floating gate drive architecture to pass DC or AC up to 1MHz from either of COIL or AC pins.

HL5501 is controlled through ENn pin and EN_POL pin. When ENn pin is driven low and EN_POL is tied to GND, the internal power FETs are enabled if either of VIN or VCC is higher than its under-voltage lockout threshold.

The HL5501 is available in 16-pin WL-CSP package.

For more detailed description of the device, please download a product brief.



  • High voltage protection load switch against positive and negative voltage
    • COIL pin AMR voltage: ± 40V
    • AC pin AMR voltage: +40V
  • Wide operating voltage up to +30V
  • Fast floating gate drive at ON state
    • Passing from DC to ~ AC 1MHz
  • Low Switch ON resistance: 90mΩ
  • Automatic power selection for internal circuitry
    • VCC: 2.4V ~ 5.5V
    • VIN: 2.4V ~ 5.5V
  • Low VIN Quiescent current
    • SW OFF current: 16uA
    • SW ON current: 10uA
  • EN_POL – ENn polarity selection pin
  • Enable control through ENn pin
  • 16 pin WLCSP, 1.66mm x 1.66mm x 0.55mm

Block Diagram

HL5501 - HMI Main Photo

For more information or a full datasheet request, please contact the factory at

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