IN Brief:
- AMD89106 and AMD89186 gate drivers share PCB footprints and register maps across 12V and 48V motor-control platforms.
- The A17810 measures steering torque and absolute angle using conductive targets rather than permanent magnets.
- The previously introduced A81481 provides integrated 48V power management, with Allegro claiming potential bill-of-materials savings of up to 50%.
Allegro MicroSystems has expanded its automotive motor-control and sensing portfolio with compatible gate drivers for 12V and 48V systems and an inductive torque sensor designed for electronically controlled steering, braking, and chassis functions.
The new automotive offering centres on the AMD89106 and AMD89186 three-phase brushless motor gate drivers and the A17810 inductive dual-angle sensor. Allegro is positioning these components alongside its A81481 power management IC, which was already introduced in October as part of the company’s robotics portfolio.
Vehicle manufacturers are introducing 48V electrical architectures to support functions requiring greater power than traditional 12V systems can efficiently distribute. Raising the nominal supply voltage allows the same electrical power to be transferred at a lower current, reducing resistive losses in conductors where other conditions remain comparable.
At four times the voltage, an equivalent power transfer requires approximately one-quarter of the current. This can reduce demands on wiring and certain power distribution components, although higher-voltage designs introduce their own requirements involving insulation, protection, switching devices, and power conversion.
The transition is especially relevant to electronically controlled chassis functions, which use electric motors and associated control electronics to provide steering assistance, braking actuation, suspension adjustment, or other mechanical responses.
Developing separate motor-control hardware for 12V and 48V vehicle platforms can increase the number of electronic control unit variants that must be designed, qualified, and maintained. Software differences may add to that workload when devices use different configuration registers or diagnostic interfaces.
Allegro’s AMD89106 and AMD89186 address part of this problem through compatible hardware and software arrangements. The AMD89106 targets 12V systems, while the AMD89186 is intended for 48V applications; both are three-phase brushless DC motor gate drivers with matching PCB footprints and register maps.
Footprint compatibility permits the same intended device location and associated connection arrangement to be used in suitable designs. A common register map allows embedded software developed for one driver to be reused when configuring and monitoring the other, reducing differences between control platforms.
That compatibility does not make the entire 12V motor-control board interchangeable with a 48V system. Power transistors, capacitors, protection devices, and other components must still be selected for the applicable electrical ratings, while switching behaviour and electromagnetic compatibility require validation at the higher operating voltage.
A gate driver controls the semiconductor switches used to supply current to an electric motor. In a three-phase brushless motor system, the electronic controller determines when the power transistors should switch to produce the required current distribution and resulting motor torque.
Driver performance influences switching timing, protection behaviour, and the information available to the controller. Allegro’s two devices integrate in-phase current sensing and digital current readback, providing measurements that can be used by motor-control software to regulate the electrical current supplied to the motor.
Accurate phase-current information supports torque control because motor torque depends on the current flowing through the machine under its operating conditions. The measurement method can also influence which current information remains available during different switching states.
Conventional arrangements may rely on measurements taken through low-side current-sensing components. Allegro positions its integrated in-phase measurement architecture as an alternative for applications where current measurement accuracy and the reduction of external circuitry are important design requirements.
The A17810 addresses a different part of the steering system. It uses inductive sensing to measure two conductive targets and calculate steering torque together with an absolute Vernier angle within the device.
Inductive sensing detects changes associated with conductive target geometry rather than measuring the magnetic field produced by permanent magnets. This allows the sensing arrangement to avoid the magnets, flux concentrators, and associated shielding required by some conventional magnetic torque sensors.
In a steering torque measurement system, mechanical displacement between two sensing positions can be related to the torque applied through the steering mechanism. The sensor must measure the corresponding angular information accurately, while the mechanical arrangement establishes how that movement relates to the applied load.
The A17810 processes two target positions to support this measurement. Allegro states that the dual-angle arrangement can reduce the need for separate angle sensors and some mechanical components used in conventional steering columns, potentially simplifying the assembled sensing system.
Removing permanent magnets also reduces dependence on magnetic field measurements in an environment containing electric motors and high-current conductors. The resulting sensor still requires suitable target design, mechanical alignment, electrical integration, and system-level validation.
Allegro identifies the device as AEC-Q100 Grade 0 qualified, supporting automotive applications requiring operation across demanding temperature conditions. Component qualification is distinct from establishing the functional safety performance of a complete steering or braking system.
The A81481 provides the power-management element of Allegro’s wider portfolio. Introduced previously for 48V robotics applications, it integrates two buck converters, five low-dropout regulators, and diagnostics intended for power supplies serving safety-related electronic control units.
Conventional 48V power arrangements can combine a separate preregulator, a lower-voltage power management device, and additional protection circuitry. The A81481 concentrates several of these functions into one IC, reducing the number of power-management components required in suitable architectures.
Allegro claims that the integration can reduce bill-of-materials costs by up to 50% compared with certain multi-device arrangements. That figure is a manufacturer estimate and will depend on the required output rails, operating conditions, external protection components, and production volumes of the completed design.
The IC includes safety diagnostics described by Allegro as capable of supporting ASIL D-related implementations. Compliance with a particular vehicle-level safety requirement must nevertheless be demonstrated through the wider control unit architecture and its defined diagnostic and fault-response measures.
The expanded portfolio is intended for steer-by-wire, electric power steering, electromechanical braking, active suspension, onboard charging, and related vehicle functions. Allegro is offering samples and evaluation support through its automotive channels and will demonstrate the technologies at electronica 2026 in Munich from 10 to 13 November.
