A3974SED Allegro Microsystems Inc, A3974SED Datasheet
A3974SED
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A3974SED Summary of contents
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DMOS Dual Full-Bridge PWM Motor 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: May 3, 2010 Recommended Substitutions: For ...
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DMOS Dual Full-Bridge PWM Motor Driver Features and Benefits ▪ ±1 continuous output rating ▪ Low r DMOS output drivers DS(on) ▪ Programmable slow, fast, and mixed current-decay modes ▪ Serial-interface controls chip functions ▪ Synchronous rectification ...
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... A3974 Selection Guide Part Number A3974SED-T 27 pieces per tube A3974SEDTR-T 450 pieces per reel Absolute Maximum Ratings Characteristic Load Supply Voltage Logic Supply Voltage Logic Input Voltage Range Reference Voltage Sense Voltage (DC) Output Current Operating Ambient Temperature Maximum Junction Temperature Storage Temperature ...
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A3974 V DD LOGIC SUPPLY CHARGE PUMP BANDGAP REG TSD CONTROL LOGIC ENABLE 1 FIXED OFF BLANK PROGRAMMABLE DECAY PWM TIMER OSC CLOCK SERIAL DATA STROBE FIXED OFF BLANK PROGRAMMABLE PWM TIMER SLEEP MODE ENABLE 2 CONTROL ...
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A3974 ELECTRICAL CHARACTERISTICS at T otherwise noted). Characteristic Output Drivers Load Supply Voltage Range Output Leakage Current Output ON Resistance Body Diode Forward Voltage Load Supply Current Control Logic Logic Supply Voltage Range Logic Input Voltage Logic Input Current (except ...
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A3974 ELECTRICAL CHARACTERISTICS at T otherwise noted), continued. Characteristic Control Logic (continued) Reference Input Current Reference Input Offset Voltage Reference Divider Ratio Gain (G ) Error (note 3) m Propagation Delay Time Crossover Delay Time Thermal Shutdown Temperature Thermal Shutdown ...
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... A3974 Serial Interface. The A3974SED is controlled via a 3-wire (clock, data,strobe) serial port. The programmable functions allow maximum fl exibility in confi guring the PWM to the mo- tor drive requirements. The serial data is written as two 20-bit words: 1 bit to select the word and 19 bits of data. The data is clocked in starting with D19 ...
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A3974 D14 Enable Logic. This bit, in conjuction with ENABLE, determines if the output drivers are in the chopped or on state. ENABLE1 D14 Mode 0 0 Chopped Chopped D15 Phase Logic. ...
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A3974 . This internally generated supply voltage is used to oper- V REG ate the sink-side DMOS outputs. V REG and in the case of a fault condition, the outputs of the device are disabled. The V terminal should be ...
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A3974 Current Sensing. To minimize inaccuracies in sensing the I current level caused by ground-trace IR drops, the sense TRIP resistor should have an independent ground return to a ground terminal of the device. For low-value sense resistors, the IR ...
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A3974 Terminal Name GND SENSE 1 NC OUT 1A NC STROBE CLOCK DATA GND REF 1 REF 2 LOGIC SUPPLY NC OUT 2A NC SENSE 2 GND LOAD SUPPLY 2 ENABLE 2 NC OUT REG SLEEP OSC ...
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A3974 17.53 ±0.13 16.59 ±0.08 0.74 ±0.08 44X 0.10 A Terminal #1 mark area Copyright ©2001-2008, 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 ...