Automotive multi-output buck-boost regulator

Allegro MicroSystems, LLC launches its new power management integrated circuit that employs a buck or buck-boost pre-regulator to effectively convert automotive battery voltages into a tightly regulated intermediate voltage, complete with control, diagnostics, and protections. The unique buck-boost design of Allegro’s A4409, allows sub 5 V input voltage operation to accommodate the latest automotive idle-stop requirements. The output of the main switching regulator supplies two 5 V LDOs, one at 300 mA and the other at 200 mA. Designed to supply power to microprocessor/DSP plus sensors, transceivers, and other loads, the A4409 is ideal for Automotive Control Units.

The Enable Input to the A4409 is compatible to a high-voltage battery level (ENBAT). Diagnostic outputs from the device include a power-on-reset output (NPOR). Long-term system reliability is increased by the use of dual internal bandgap voltage references, one for regulation and one for fault-checking.