A4938EETTR-T Allegro Microsystems Inc, A4938EETTR-T Datasheet
A4938EETTR-T
Specifications of A4938EETTR-T
Related parts for A4938EETTR-T
A4938EETTR-T Summary of contents
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Features and Benefits ▪ Drives 6 N-channel MOSFETs ▪ Synchronous rectification for low power dissipation ▪ Internal UVLO and thermal shutdown circuitry ▪ Hall element inputs ▪ PWM current limiting ▪ Dead time protection ▪ FG outputs ▪ Standby mode ...
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... Description (continued) shutdown with hysteresis, undervoltage lockout, and dead time protection. Special power-up sequencing is not required. Operating temperature range is –40°C to 85°C. Selection Guide Part Number A4938EETTR-T 1500 pieces per reel Absolute Maximum Ratings Characteristics Load Supply Voltage Motor Phase Output ...
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A4938 0.1 μF Lock CLD Detect HBIAS 2 kΩ HA+ 0.1 μF HALL HA- Commun- HB+ ication HALL Logic HB- HC+ HALL HC- FG1 BRAKEZ System DIR Logic ENABLE V IN GND Terminal List Number Name 1 HA+ Hall input ...
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A4938 ELECTRICAL CHARACTERISTICS Characteristics Supply Voltage Range Motor Supply Current HBIAS HBIAS Current Limit Control Logic Logic Input Voltage Logic Input Pull-Up Input Pin Glitch Reject ENABLE Standby Pulse Propagation Delay HBIAS Wake-up Delay, Standby Mode Gate Drive High-Side Gate ...
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A4938 ELECTRICAL CHARACTERISTICS Characteristics Hall Logic Hall Input Current Common Mode Input Range AC Input Voltage Range Hall Thresholds Hall Threshold Hysteresis Pulse Reject Filter FG FG Output Saturation Voltage FG Leakage Current *Typical data are for initial design estimations ...
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A4938 Logic States Table (See timing charts, below Don’t Care (can 0 high impedance Condition – – – – Forward D – ...
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A4938 Power-up and Standby Modes Timing Diagram VBB Charge Pump HBIAS Voltage ENABLE Power-up and Standby Modes Timing Diagram VBB V +7 Charge Pump 7.5 V HBIAS Voltage ENABLE 3-Phase Brushless DC Motor Pre-Driver V BBUV Standby Mode ...
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A4938 Load current is regulated by an internal Current Regulation fixed off-time PWM control circuit. When the outputs of the full bridge are turned on, current increases in the motor winding until it reaches a value given by: ...
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A4938 holding ENABLE high for longer than 3 ms. Note that the state of BRAKEZ does not affect Standby mode. The internal charge pump is used to generate a Charge Pump supply above V to drive the high-side MOSFETs. The ...
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A4938 29X 0.08 C +0.05 0.25 –0.07 +0.20 0.55 –0. Copyright ©2010, Allegro MicroSystems, Inc. Allegro MicroSystems, Inc. reserves the right to make, from time to time, such de par tures from the detail spec ...