Buck-boost regulator designed to power automotive sensors

30th August 2017

Anna Flockett

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Datasheet

The release of a new wide input 5V output regulator has been announced by Allegro MicroSystems Europe, which is 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 5V.

Allegro’s A4480 incorporates a multi-mode charge pump pre-regulator, followed by a 5V LDO. This enables operation with input voltages from 3.5-28V (with 40V protection), while maintaining a 5V 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 optimised solution.

The enable pin (ENB) is rated to operate at up to 40V, 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% matt tin leadframe plating.