Allegro MicroSystems A4941
The A4941 three-phase motor driver incorporates BEMF sensing to eliminate the requirement for Hall sensors in fan applications. The A4941 is provided in a 16-pin TSSOP package (suffix LP) with an exposed thermal pad. It is lead (Pb) free, with 100% matte tin leadframe plating.| Part No. | A4941 |
|---|---|
| Datasheet | A4941 Download |
| Manufacturer |  Allegro MicroSystems |
| Description | Three-Phase Sensorless Fan Driver |
| Buy | Stock & Price |
FEATURES AND BENEFITS
● Sensorless (no Hall sensors required)● Soft switching for reduced audible noise
● Minimal external components
● PWM speed input
● FG speed output
● Low power standby mode
● Lock detection
● Optional overcurrent protection
● Variant A automotive qualified to AEC-Q100 Grade 2 PACKAGE: 16-pin TSSOP with exposed thermal pad (suffix LP)
DESCRIPTION
A pulse wave modulated (PWM) input is provided to control motor speed, allowing system cost savings by eliminating external variable power supply. PWM input can also be used as an on/off switch to disable motor operation and place the IC into a low power standby mode. Not to scale Functional Block Diagram 12 V VCP 0.1 µF CP1 0.1 µF CP2 10 µF VBB SLEW PWM 25 kHz VBB O/C FC TEST 10 kΩ FG +VINT Soft Switch Control Logic OSC Timers Startup OSC Sequencer (Direction) CDCOM Adaptive Commutation Delay FCOM Charge Pump 3-Phase Half Bridges OCP OUTA OUTB M OUTC SENSE 0.167 Ω GND OUTA CTAP OUTB OUTC GND – + – + – + BEMF Comparator A4941-DS, Rev.
