8902A Datasheet (Allegro MicroSystems) - 3-PHASE BRUSHLESS DC MOTOR CONTROLLER/DRIVER WITH BACK-EMF SENSING

8902A, 3-PHASE BRUSHLESS DC MOTOR CONTROLLER/DRIVER WITH BACK-EMF SENSING

Power Outputs.

The power outputs of the A8902CLBA are n-channel DMOS transistors with a total source plus sink rDS(on) of typically 1 Ω.

Internal charge pump boost circuitry provides voltage above supply for driving the high-side DMOS gates.

Intrinsic ground clamp and flyback diodes provide protecti

8902 A 3-PHASE BRUSHLESS DC MOTOR CONTROLLER/DRIVER WITH BACK-EMF SENSING LOAD SUPPLY C D2 C WD CST OUTA GROUND GROUND OUT B OUT C CENTERTAP BRAKE C RES 1 2 V BB COMMUTATION DELAY 24 23 C D1 DATA IN CLOCK CHIP SELECT RESET GROUND GROUND DATA OUT OSCILLATOR LOGIC SUPPLY SECTOR DATA FILTER Data Sheet 26301.2 SERIAL PORT 3 4 5 6 7 8 9 9 10 11 12 BOOST CHARGE PUMP 22 21 20 19 18 The A8902CLBA is a three-phase brushless dc motor controller/ driver for use in 5 V or 12 V hard-disk drives.

8902A Features

* and modes of operation, such as the speed control parameters, startup current limit, sleep mode, diagnostic modes, and others. The A8902CLBA is fabricated in Allegro’s BCD (Bipolar CMOS DMOS) process, an advanced mixed-signal technology that combines bipolar, analog and digital CMOS, and DMOS power