Allegro Microsystems, LLC Announces Wide Input Voltage Inductorless Buck-boost Regulator

5V @50mA with Operation Down to 3.5Vin and Harness Short Protection

Allegro MicroSystems, LLC announces the release of a new wide input 5 V output regulator designed to power automotive sensors and low power uControllers. It can also be used for non-automotive applications where the input voltage could be above or below 5 V.

Allegro’s A4480 incorporates a unique multi-mode charge pump pre-regulator, followed by a 5V LDO. This enables operation with input voltages from 3.5 to 28 V (with 40V protection), while maintaining a 5 V output voltage. Compared to traditional LDO solutions, the efficiency across input range is improved, and VIN < VOUT operation is enabled. Furthermore, as opposed to traditional switching solutions no inductor, diode, or external switching element is required in this simple, low component-count optimized solution.

The enable pin (ENB) is rated to operate at up to 40 V, so it can be connected directly to VIN (e.g., vehicle battery). The IC includes an open-drain Power OK (POK) output, and protection features include input undervoltage lockout (UVLO), foldback overcurrent protection, output under/overvoltage protections (UV/OVP), and thermal shutdown (TSD). In addition, the output is protected from a short-to-battery event, which is a critical feature when driving loads connected via a wiring harness.

The A4480KLJTR-T device is available in an 8-pin eSOIC package with exposed pad for enhanced thermal dissipation. It is lead (PB) free, with 100% matte tin leadframe plating and priced at $0.90 in quantities of 1,000.

Features & Benefits:

  • Automotive AEC-Q100 qualified
  • Wide operating range of 3.5 to 28 V, with 40 V load dump rating
  • Linear regulator output with foldback short-circuit and short-to-battery protection
  • Boost function to maintain output when input is low
  • Power OK (POK) flag
  • High-voltage logic-level enable input (ENB) for microprocessor or ignition control
  • Pin-to-pin and pin-to-ground tolerant at every pin
  • Allegro Sensor Bias LDO


  • Microcontroller power
  • Transceivers (CAN, LIN, etc.) power supplies
  • Sensors

Please click here to download a copy of the A4480 wide input voltage regulator datasheet.