a8902 Allegro MicroSystems, Inc., a8902 Datasheet
a8902
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a8902 Summary of contents
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... 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 devices. The A8902CLBA is provided in a 24-lead wide-body SOIC batwing package. It provides for the smallest possible construction in surface-mount applications. ...
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... WATCHDOG TIMER CHARGE PUMP MUX TSD C/W JT 125 150 Dwg. GP-019C 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1992, 1995 Allegro MicroSystems, Inc. C RES BRAKE BOOST CHARGE BRAKE PUMP LOAD 1 SUPPLY OUT A 8 ...
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Characteristic Symbol Logic Supply Voltage Logic Supply Current Load Supply Voltage Thermal Shutdown Thermal Shutdown Hysteresis Output Drivers Output Leakage Current Total Output ON Resistance r DS(on) (Source + Sink + Output Sustaining Voltage V DS(sus) Clamp ...
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BRUSHLESS DC MOTOR CONTROLLER/DRIVER Characteristic Symbol C Current WD C Threshold Voltage WD Max. FLL Oscillator Frequency I (MAX) OUT BRAKE Threshold BRAKE Hysteresis Current Transconductance Gain Centertap Resistors Back-EMF Hysteresis CHIP SELECT CLOCK DATA Minimum CHIP SELECT ...
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Term. Terminal Name 1 LOAD SUPPLY OUT A 6-7 GROUND 8 OUT B 9 OUT C 10 CENTERTAP 11 BRAKE 12 C RES 13 FILTER 14 SECTOR DATA 15 LOGIC ...
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... BRUSHLESS DC MOTOR CONTROLLER/DRIVER Power Outputs. The power outputs of the A8902CLBA are n-channel DMOS transistors with a total source plus sink r of typically 1 . Internal charge pump boost circuitry provides voltage above supply for driving the high-side DMOS gates. Intrinsic ground clamp and flyback diodes provide ...
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Adaptive Commutation Delay. The adaptive commutation delay circuit uses the back-EMF zero-crossing indicator signal (FCOM) to determine an optimal commuta- tion time for efficient synchronous operation. This circuit commutates the outputs, delayed from the last zero crossing, using two external ...
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... BRUSHLESS DC MOTOR CONTROLLER/DRIVER Current Control. The A8902CLBA provides linear current control via the FILTER terminal, an analog voltage input. Maximum current limit is also provided, and is controlled in four steps via the serial port. Output current is sensed via an internal sense resistor (R ...
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... Serial Port. The serial port functions to write various operational and diagnostic modes to the A8902CLBA. The serial port DATA IN is enabled/disabled by the CHIP SELECT terminal. When CHIP SE- LECT is high the serial port is disabled and the chip is not affected by changes in data at the DATA IN or CLOCK terminals. ...
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... FAULT Braking. A dynamic braking feature of the A8902CLBA shorts the three motor windings to ground. This is accomplished by turning the three source drivers OFF and the three sink drivers ON. Activation of the brake can be implemented through the BRAKE input or through the D2 bit in the serial port. The supply voltage for the brake circuitry ...
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MOTOR CONTROLLER/DRIVER 0.050 3 0.6141 BSC 0.5985 NOTE 1 NOTE 3 0.0040 MIN . 1.27 3 15.60 BSC 15.20 ...
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... MOTOR CONTROLLER/DRIVER The products described here are manufactured under one or more U.S. patents or U.S. patents pending. Allegro MicroSystems, Inc. reserves the right to make, from time to time, such departures from the detail specifications as may be required to permit improvements in the performance, reliability, or manufacturability of its products. Before placing an order, the user is cautioned to verify that the information being relied upon is current ...