Overview: Allegro Targets the 800V Data Center Transition

Allegro MicroSystems, Inc. (Nasdaq: ALGM) on October 27, 2026 announced a portfolio expansion aimed squarely at the power and thermal bottlenecks of AI data centers. Announced from the company's Manchester, N.H. headquarters, the lineup spans high-isolation current sensors, an isolated silicon carbide gate driver and an updated code-free 48V motor driver. The common thread is architectural: as racks densify around accelerators that draw sharply varying current, the power delivery path itself has to be re-engineered, and Allegro is positioning sensing and control silicon at the points where conversion losses and thermal load accumulate.

The products are explicitly framed around two concurrent transitions — the move from 54V to 800V DC power distribution, and the adoption of 48V cooling architectures for fans and pumps. Allegro describes the goal as increasing power density while helping designers manage energy use, heat dissipation and equipment size.

Market Context: Why 800V Distribution Is Being Adopted

The shift from 54V to 800V DC distribution is a response to scale rather than a preference for novelty. Higher distribution voltages reduce the current required to deliver a given amount of power, which in turn reduces resistive losses along the delivery path and eases the copper and busbar constraints inside a rack power shelf. For AI workloads, the added complication is dynamic: power demand can change abruptly as accelerators move between compute phases, placing a premium on measurement speed and protection response rather than steady-state accuracy alone.

Allegro's portfolio is organized around that reality. The company lists five design objectives for the new parts: safely monitoring and controlling 800V systems, reducing energy lost during conversion, fitting more power capability into limited board and rack space, improving 48V cooling fan efficiency and reliability, and simplifying system design to shorten development time.

Technical Details: 6000V Isolation in Current Sensing

The sensing element of the announcement is the availability of the ACS37030 and ACS37002 current sensors in wide-body packages using a high comparative tracking index (CTI) mold compound. That combination enables 6000V of galvanic isolation, a specification directly relevant to electrical safety in high-voltage systems where the measurement point sits on the high side of an 800V rail.

Allegro positions the fast, accurate current measurement of these devices as the mechanism for protecting power supplies, battery backup units and capacitor banks when AI workloads create sudden changes in power demand. Equally important is physical fit: the company states the compact package allows customers to support 800V systems without increasing the size of the rack power shelf or power supply unit — a constraint that matters because rack real estate is increasingly allocated to compute rather than power conversion.

Gate Drive: The AHV85311 and SiC Simplification

On the conversion side, the AHV85311 Power-Thru isolated gate driver targets silicon carbide FETs. Its architectural contribution is the elimination of a separate isolated power supply, which Allegro says can reduce circuit-board space by up to 50%. That reduction is framed as enabling smaller power supplies and faster solid-state circuit breakers for 800V data center systems — both elements of a protection strategy that must act quickly when fault currents rise in a high-voltage bus.

SiC devices are attractive in this context because they support efficient high-voltage switching, but their gate drive requirements have historically added isolation complexity. Collapsing the isolated bias supply into the driver is therefore a system-level simplification as much as a component-level one.

Thermal Management: The QuietMotion A89333 for 48V Cooling

Allegro identifies cooling as a major source of energy consumption in AI data centers, and addresses it with an improved version of the code-free QuietMotion A89333 motor driver. The device is designed for 48V server cooling fans and includes built-in control technology that automatically manages changing airflow conditions, without requiring customers to develop complex motor-control software.

  • Supports the compact fans used in 1U, 2U and 4U servers
  • Removes the need for bespoke motor-control firmware development
  • Extends to pumps used in liquid cooling systems

The practical value is twofold: reduced development effort for system designers, and more reliable fan operation as computing density increases and airflow impedance changes.

Customer Validation: Acbel Polytech

Power solution provider Acbel Polytech has integrated Allegro's high-speed current sensors into its latest high-density power solutions for AI data centers, supporting precise power control and system protection. Rossi Lo, Head of Research and Development at Acbel, framed the requirement in terms of architecture evolution: as power distribution moves to higher power and voltage levels, precise power control and rapid system protection become increasingly critical, with current sensing playing a key role.

Troy Coleman, Senior Vice President of Products at Allegro, characterized the challenge as using less energy and operating more efficiently while safely delivering significantly more computing power, and described the new parts as addressing critical system points from high-voltage conversion and protection through intelligent cooling.

Market Sizing and Adjacent Applications

Allegro projects, based on third-party data and internal estimates, that its serviceable addressable market for AI data centers will reach $1.7 billion by fiscal 2031. The company also notes that the same products suit industrial automation, robotics and automotive on-board charging systems, where efficient 48V operation, high-voltage isolation and compact design are increasingly valued. Allegro will showcase the technologies at electronica 2026 in Munich this November, at Hall C6, Booth 129.

Implications and Outlook

The announcement reflects a broader pattern in AI infrastructure: as distribution voltages rise to 800V and cooling loops migrate to 48V, the semiconductor content per rack shifts toward isolation, sensing and integrated motor control rather than raw conversion alone. Allegro's bet is that the safety and measurement layer — 6000V isolation, fast current sensing, gate drive simplification and code-free fan control — becomes a decisive design consideration as operators pursue efficiency and sustainability targets. Whether the 800V transition proceeds at the pace the company's fiscal 2031 market estimate implies will depend on how quickly OEMs redesign power shelves and protection schemes, but the component building blocks for that migration are now being positioned commercially.