A8904SLB Allegro Microsystems Inc, A8904SLB Datasheet
A8904SLB
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A8904SLB Summary of contents
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Brushless DC Motor Controller/Driver Discontinued Product These parts are no longer in production The device should not be purchased for new design applications. Samples are no longer available. Date of status change: November 1, 2010 Recommended Substitutions: For existing ...
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Brushless DC Motor Controller/Driver Features and Benefits ▪ Pin-for-pin replacement for A8902CLBA ▪ Start-up commutation circuitry ▪ Sensorless commutation circuitry ▪ Option of external sector data tachometer signal ▪ Option of external speed control ▪ Oscillator operation up to ...
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... A8904 Selection Guide Part Number A8904SLBTR-T A8904SLPTR-T 28-pin TSSOP Absolute Maximum Ratings Characteristic Load Supply Voltage Logic Supply Voltage Logic Input Voltage Range Output Current Peak Output Current (Brake) I Period OUT(BRK) Operating Ambient Temperature Maximum Junction Temperature Storage Temperature 3-Phase Brushless DC Motor Controller/Driver ...
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A8904 LB Package LOAD COMMUTATION 1 V SUPPLY BB DELAY OUT GROUND GROUND 7 OUT B 8 MUX 9 OUT C 9 FLL V CENTERTAP 10 BOOST CHARGE ...
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A8904 LB (SOIC) Package Thermal Characteristics Characteristic Package Thermal Resistance *Additional thermal information available on the Allegro website 3-Phase Brushless DC Motor Controller/Driver Symbol Test Conditions* Package LB, 4-layer PCB based on JEDEC standard Package LB, 2-layer PCB with 1 ...
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A8904 ELECTRICAL CHARACTERISTICS at T Characteristic Logic Supply Voltage Logic Supply Current Undervoltage Threshold Load Supply Voltage Load Supply Current Thermal Shutdown Thermal Shutdown Hysteresis Output Drivers Output Leakage Current Total Output ON Resistance (source + sink + R ) ...
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A8904 ELECTRICAL CHARACTERISTICS (continued Characteristic C Current WD C Threshold Voltage WD Max. FLL Oscillator Frequency Oscillator High Duration Oscillator Low Duration Maximum Output Current I OUT Transconductance Gain Centertap Resistors Back-EMF Threshold with respect ...
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A8904 A. Minimum CHIP SELECT setup time before CLOCK rising edge ........... 100 ns B. Minimum CHIP SELECT hold time after CLOCK rising edge ................ 150 ns C. Minimum DATA setup time before CLOCK rising edge .......................... 150 ns D. ...
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A8904 Terminal Name Function LOAD SUPPLY V ; the motor supply One of two capacitors used to generate the ideal commutation points from D2 the back-EMF zero crossing points. C Timing capacitor used ...
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A8904 Overview of operation. Each electrical revolution contains six states that control the three half-bridge outputs. Optimized switching from state to state is achieved through the adaptive commutation circuitry. During any state, one output is high, one is low and ...
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A8904 (output crossing through centertap). If the correct polarity of back-EMF is not detected, a watchdog circuit commutates the output until the correct back-EMF is detected. Correct back- EMF sensing is indicated by the FCOM signal, which toggles every time ...
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A8904 Watchdog-triggered commutation After the watchdog capacitor C charges to the V WD and if the correct polarity of back-EMF signal is detected, the back-EMF detection circuit discharges C waveform above) and the circuit is ready to detect the next ...
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A8904 Speed error signals A speed error signal is created by integrating the differences between the TACH and REF signal. If the TACH signal goes low before the REF signal then an ERROR FAST is produced and if the TACH ...
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A8904 In applications where both internal and external TACH sig- nals are used important to only switch between modes when the SYNC signal on DATA OUT is low. This ensures the speed control information that is being processed ...
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A8904 the default condition for A8902-A operation. The only consid- eration when using the A8904 in an A8902-A application is to ensure the minimum CHIP SELECT high time is at least 500 ns Sleep/Run Mode; LOW = Sleep, ...
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A8904 Braking. A dynamic braking feature of the A8904 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 ...
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A8904 3-Phase Brushless DC Motor Controller/Driver Typical application (LB package) with Back EMF Sensing Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 16 ...
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A8904 15.40±0. 24X 0.10 C 0.41 ±0.10 1.27 For reference only Pins 6 and 7, and 18 and 19 internally fused Dimensions in millimeters (Reference JEDEC MS-013 AD) Dimensions exclusive of mold flash, gate burrs, and ...
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A8904 Copyright ©2003-2008, Allegro MicroSystems, Inc. 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 de par tures from the ...