A3989 Allegro MicroSystems, A3989 Datasheet
A3989
Related parts for A3989
A3989 Summary of contents
Page 1
... Special power up sequencing is not required. The A3989 is supplied in a leadless 6 mm × × 0.9 mm, 36 pin QFN package with exposed power tab for enhanced thermal performance. The package is lead (Pb) free, with 100% matte tin www ...
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... A3989 Bipolar Stepper and High Current DC Motor Driver Selection Guide Part Number A3989SEV-T 61 pieces per tube A3989SEVTR-T 1500 pieces per reel Absolute Maximum Ratings Characteristic Symbol Load Supply Voltage V BB Logic Supply Voltage V DD Output Current * I OUT Logic Input Voltage Range ...
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... A3989 Bipolar Stepper and High Current DC Motor Driver VDD OSC PHASE1 I01 I11 PHASE2 I02 I12 Sense1 VREF1 3 VREF2 3 Sense 2 PHASE3 ENABLE MODE Sense 3 VREF3 3 Functional Block Diagram 0.1 µF 0.1 µ DMOS Full Bridge 1 CHARGE PUMP V CP Control Logic Stepper Motor ...
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... A3989 Bipolar Stepper and High Current DC Motor Driver ELECTRICAL CHARACTERISTICS 1 , valid at T Characteristics Load Supply Voltage Range Logic Supply Voltage Range VDD Supply Current Output On Resistance (dc motor driver) Output On Resistance (stepper motor driver Outputs f Output Leakage VBB Supply Current Control Logic ...
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... Synchronous Rectification triggered by an internal fixed off-time cycle, load current will recirculate. The A3989 synchronous rectification feature will turn on the appropriate MOSFETs during the current decay. This effectively shorts the body diode with the low R significantly lowers power dissipation ...
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... A3989 Bipolar Stepper and High Current DC Motor Driver is detected, synchronous rectification is turned off to prevent reversal of the load current. Mixed Decay Operation The stepper driver operates in mixed decay mode. Referring to figure 2, as the trip point is reached, the device goes into fast decay mode for 30.1% of the fixed off-time period ...
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... A3989 Bipolar Stepper and High Current DC Motor Driver 100.0 66.7 Phase 1 0 (%) –66.7 –100.0 100.0 66.7 Phase 2 0 (%) –66.7 –100.0 Full step 2 phase Modified full step 2 phase Figure 3. Step Sequencing for Full-Step Increments. Step Sequencing Diagrams 100.0 66.7 Phase 1 0 (%) –66.7 –100.0 100.0 66.7 Phase 2 ...
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... A3989 Bipolar Stepper and High Current DC Motor Driver 100.0 66.7 33.3 Phase 1 0 (%) –33.3 –66.7 –100.0 100.0 66.7 33.3 Phase 2 0 (%) –33.3 –66.7 –100.0 Step Sequencing Settings Full 1 Denotes modified step mode Figure 5. Decay Modes for Quarter-Step Increments Phase 1 1/4 I0x ...
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... A3989 Bipolar Stepper and High Current DC Motor Driver Logic Timing Diagram, DC Driver ENB PH MODE V BB OUTA OUTB OUT 0 A OutA A Charge Pump and VREG Power-up Delay ( 200 µ OutB ...
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... Figure 5. Printed circuit board layout with typical application circuit, shown at right. The copper area directly under the A3989 (U1) is soldered to the exposed thermal pad on the underside of the device. The thermal vias serve also as electrical vias, connecting it to the ground plane on the other side of the PCB , so the two copper areas together form the star ground. ...
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... A3989 Bipolar Stepper and High Current DC Motor Driver Terminal List Table Number – Pin-out Diagram PHASE1 I12 28 18 I11 PHASE2 29 17 GND GND 30 16 ...
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... A3989 Bipolar Stepper and High Current DC Motor Driver Preliminary dimensions, for reference only (reference JEDEC MO-220VJJD-1, except exposed thermal pad) Dimensions in millimeters U.S. Customary dimensions (in.) in brackets, for reference only Dimensions exclusive of mold flash, gate burrs, and dambar protrusions Exact case and lead configuration at supplier discretion within limits shown ...