A4931MET-T

Overview

The A4931MET-T is a three-phase brushless DC (BLDC) motor pre-driver manufactured by Allegro MicroSystems. It operates within a supply voltage range of 8 V to 37.5 V and supports a maximum load voltage of 24 V. The device features a 28-pin QFN package with dimensions of 5 mm x 5 mm x 0.9 mm. It functions as a controller for commutation and direction management, utilizing power MOSFET technology. The operational temperature range spans from -20 °C to +105 °C.

Feature Summary

• Provides integrated commutation logic driven by three Hall effect inputs spaced 120 degrees apart.
• Incorporates synchronous rectification to reduce power loss during current decay phases.
• Includes fixed off-time PWM current control to limit inrush currents effectively.

Applications

• Three-phase BLDC motor control systems
• Fan and pump speed regulation applications
• Industrial automation motor drives

Procurement Notes

Verify the exact suffix against official Allegro documentation, as variations such as METTR-T may indicate specific tape-and-reel packaging configurations. Confirm RoHS compliance status and moisture sensitivity level requirements prior to integration into surface-mount assembly processes.

Selection Notes

Select this component for designs requiring compact footprint solutions with integrated Hall sensing logic. Ensure external N-channel MOSFETs are compatible with the driver's gate drive capabilities. Validate thermal performance within the specified ambient temperature range using the exposed pad for heat dissipation.

Part Context

This part belongs to the A4931 family of motor drivers designed for low-voltage BLDC applications. It serves as a pre-driver stage, controlling external power switches rather than containing internal high-current FETs. The design emphasizes efficiency through synchronous rectification and robust protection mechanisms.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided source material. Consult Allegro MicroSystems technical support for direct replacements or cross-reference with similar pre-driver architectures if pin compatibility is required.

FAQ

Does the A4931MET-T contain internal power FETs?

No, it is a pre-driver that controls external N-channel power MOSFETs.

How is the motor commutation determined?

Commutation logic is derived from three Hall effect sensor inputs spaced 120 degrees apart.