48V Power Integration and Precision Sensors for Humanoid Robots

Allegro MicroSystems is releasing new 48V power architectures and precision motion sensors developed for Physical Artificial Intelligence (PAI) applications. The integrated solutions are designed to address size, weight, and safety constraints in humanoid robotics and human-robot collaborative environments.

Advancing 48V Power Supply Integration in Confined Architectures
Humanoid robots increasingly utilize 48V bus architectures to minimize wiring mass and reduce resistive losses throughout their mechanical structures. However, safely stepping down higher voltages in restricted spaces poses significant thermal and spatial challenges. The A81481 power management integrated circuit (PMIC) addresses this engineering bottleneck by managing power and safety functions directly from the 48V bus, eliminating the need for external pre-regulators.

Packaged in a 6 × 6 mm footprint, the PMIC integrates two buck regulators, five low-dropout (LDO) outputs, and an ASIL-D compliant three-circuit watchdog diagnostic system. This direct power management architecture supplies distributed sensor groups, simplifies printed circuit board routing, and reduces the overall system footprint and bill of materials cost by approximately 50 percent.

Addressing High-Torque Joint Accuracy and Magnetic Interference
High-torque actuators located in robotic shoulders, hips, and knees require highly accurate positioning under constant mechanical stress. The A17802 and A17803 inductive position sensors maintain measurement reliability by tolerating air-gap variations through on-chip compensation and advanced filtering algorithms. Their inherent immunity to stray magnetic fields eliminates the necessity for heavy, space-consuming magnetic shielding, further optimizing joint weight. To fit heavily constrained actuator designs, the A17803 is housed in an ultra-compact QFN package.

Micro-Joint Dexterity for Robotic End Effectors
To support micro-joint manipulation in robotic hands and fingers, the portfolio utilizes solid-state technologies as a compact alternative to traditional wire-wound resolvers and optical encoders. The CT310 tunneling magnetoresistance (TMR) angular sensor delivers sub-degree angular accuracy within a 2 × 2 mm DFN package, providing high resistance to contamination, mechanical shock, and runout errors. Alongside it, the A33023 Hall effect sensor offers low latency processing and digital output configurability to support stringent functional safety diagnostics.

Sarcomere Dynamics Inc. is integrating these motion controllers and power ICs into its Scorpion robotic gripper.

"Precise motion control, accurate measurement, and efficient power management are essential for advanced robotic manipulation," stated Harpal JS Mandaher, CEO of Sarcomere Dynamics Inc. "We plan to continue this collaboration with our next-generation ARTUS Dex, a 24-degree-of-freedom robotic hand designed to deliver near-human-like dexterity in advanced Physical AI applications."

"In stationary industrial robots, weight and size are less of a constraint, as large-gauge cables, large external drives, and liquid cooling systems can be used," noted Andreas Friedrich, Senior Director of Technology and Strategy at Allegro MicroSystems. "In autonomous humanoid robots with more than 30 degrees of freedom, every gram and every millimeter counts. By combining 48V power management, robust drivers, and compact inductive and TMR sensors, we provide integrated technology building blocks designed to maximize torque and control tight mechanical tolerances."

Additional Context
This section details technical specifications and competitive benchmarking not included in the original news release.

In the autonomous robotics sector, the shift to 48V power distribution is standardizing across developers aiming to optimize power-to-weight ratios. The Allegro A81481 PMIC competes with highly integrated 48V buck controllers and power management solutions from Texas Instruments and Analog Devices. While competitors frequently focus on high-efficiency GaN-integrated solutions for motor drives, Allegro’s direct integration of ASIL-D safety diagnostics alongside the dual buck and LDO outputs specifically targets the strict functional safety requirements of collaborative robotics operating near humans.

For angular position sensing, the XtremeSense TMR technology competes directly with TMR sensors from Melexis and Infineon Technologies. Magnetic stray field immunity has become a primary benchmark for robotic joint encoders. Allegro’s integration of on-chip compensation for air-gap variations provides a measurable advantage in reducing calibration time during robotic assembly compared to traditional optical encoders, which require clean operating environments and highly precise mechanical alignment.

Edited by Aishwarya Mambet, Induportals Editor, with AI assistance.

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