A4938EETTR-T

Overview

The A4938EETTR-T is a three-phase brushless DC (BLDC) motor pre-driver designed to drive six N-channel power MOSFETs in a bridge configuration. It integrates Hall element inputs for commutation, a sequencer, fixed off-time PWM current control, and locked-rotor detection. The device operates on a supply voltage of 8.5V to 30V and supports an ambient temperature range of -40°C to 85°C. It is housed in a 28-terminal QFN package measuring 5mm x 5mm with an exposed thermal pad.

Feature Summary

• Integrates three Hall-element inputs and a sequencer for direct commutation control
• Provides high-current gate drive for external all N-channel power MOSFETs
• Includes internal circuit protection such as thermal shutdown with hysteresis and undervoltage lockout
• Features synchronous rectification to reduce power dissipation during current decay

Applications

• Three-phase BLDC motor control systems
• Fan and pump drives requiring commutation management
• Industrial automation equipment using N-channel MOSFET bridges

Procurement Notes

Verify component authenticity through authorized channels due to end-of-life status. Confirm the specific suffix matches the required package and tape/reel specifications. Check for manufacturer-recommended replacements if long-term availability is critical. Ensure handling procedures account for moisture sensitivity level 2 requirements during storage and assembly.

Selection Notes

Select this component when designing three-phase BLDC applications requiring integrated Hall sensing and commutation logic. It is suitable for designs utilizing external N-channel MOSFETs where gate drive current must be scaled by external device capabilities. Consider the 28-QFN footprint constraints and thermal pad requirements for PCB layout optimization.

Part Context

This part belongs to the Allegro MicroSystems A4938 family of BLDC pre-drivers. It is distinct from stepper motor drivers like the A4988 or other PMICs in the portfolio. The EETTR-T suffix indicates the specific 28-QFN package and tape-and-reel packaging format used for surface-mount assembly.

Replacement Considerations

Allegro Microsystems recommends the AMT49413GEVATR as a replacement for this discontinued part.