Allegro combines 48V power conversion and safety monitoring in one PMIC
Allegro MicroSystems is expanding its robotics offering around a 48V power-management IC that combines conversion, sensor supplies and safety monitoring in a single package.
The A81481 takes power directly from a 48V bus, removing the external pre-regulator used in some multi-chip arrangements. Its two buck stages provide 12.5V and 5.4V outputs, with five protected LDO outputs supplying lower-voltage circuitry. Allegro specifies a 12–72V operating range and an 80V absolute maximum rating.
That distinction matters in a machine full of inductive loads. Nominal bus voltage is only one electrical condition; a regulator also has to operate within the system’s defined transient environment. The absolute maximum figure is a limit, not a second operating range.
The IC’s triple-watchdog architecture monitors the host processor, while its protected LDOs can supply remote sensors, encoders and CAN circuitry. The company describes the part as a hardware safety element developed out of context with ASIL D capability. That supports its use within a safety architecture; it does not establish the safety integrity of a complete robot by itself.
In a 6 × 6mm package, the appeal is the reduction in circuitry around a remote sensing or control assembly. A 48V distribution bus can reduce current for a given transmitted power, but local electronics still require several much lower rails. Putting those conversions together can remove board area, external connections and separate monitoring devices.
Allegro claims roughly a 50% reduction in system footprint and bill-of-materials cost against the multi-chip approach it describes. That comparison depends on the functions being replaced and the surrounding design, rather than representing a fixed saving on every control board.
The wider portfolio includes inductive and magnetic position sensors, but these perform a separate task from the PMIC. Allegro is offering samples and evaluation support for the robotics building blocks, with the power and sensing portfolio due to appear at electronica in Munich, Hall C6, stand 129.
