A4987SESTR-T Allegro Microsystems Inc, A4987SESTR-T Datasheet
A4987SESTR-T
Specifications of A4987SESTR-T
Related parts for A4987SESTR-T
A4987SESTR-T Summary of contents
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DMOS Dual Full-Bridge PWM Motor Driver Features and Benefits ▪ Low R outputs DS(ON) ▪ Internal mixed current decay mode ▪ Synchronous rectification for low power dissipation ▪ Internal UVLO ▪ Crossover-current protection ▪ 3.3 and 5 V compatible logic ...
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... A4987 Selection Guide Part Number A4987SESTR-T 24-pin QFN with exposed thermal pad A4987SLPTR-T 24-pin TSSOP with exposed thermal pad Absolute Maximum Ratings Characteristic Load Supply Voltage Output Current Logic Input Voltage Logic Supply Voltage VBBx to OUTx Sense Voltage Reference Voltage Operating Ambient Temperature ...
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A4987 REGULATOR VREG 0.22 μF Sense2 DAC PWM Latch OSC V BLANKING REF Mixed Decay VDD IN01 IN02 PH1 CONTROL LOGIC IN11 IN12 PH2 SLEEP PWM Latch BLANKING Mixed Decay REF V REF DMOS Dual Full-Bridge PWM Motor Driver With ...
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A4987 ELECTRICAL CHARACTERISTICS Characteristics Output Drivers Load Supply Voltage Range Logic Supply Voltage Range Output On Resistance Body Diode Forward Voltage Motor Supply Current Logic Supply Current Control Logic Logic Input Voltage Logic Input Current Logic Input Pull-down Logic Input ...
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A4987 THERMAL CHARACTERISTICS may require derating at maximum conditions Characteristic Package Thermal Resistance *In still air. Additional thermal information available on Allegro Web site. DMOS Dual Full-Bridge PWM Motor Driver Symbol Test Conditions* ES package; estimated, on 4-layer PCB, based ...
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A4987 The A4987 is designed to operate one Device Operation. stepper motor in full, half, or quarter step mode. The currents in each of the output full-bridges, all N-channel DMOS, are regu- lated with fixed off-time pulse width modulated (PWM) ...
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A4987 (CP1 and CP2). The charge pump is used to Charge Pump generate a gate supply greater than that of VBB for driving the source-side FET gates. A 0.1 μF ceramic capacitor, should be connected between CP1 and CP2. In ...
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A4987 V STEP 100.00 70.71 I OUT 0 –70.71 –100.00 I OUT Symbol I Figure 4. Current Decay Modes Timing Chart DMOS Dual Full-Bridge PWM Motor Driver See Enlargement A Enlargement PEAK Characteristic t Device fixed ...
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A4987 Layout. The printed circuit board should use a heavy ground- plane. For optimum electrical and thermal performance, the A4987 must be soldered directly onto the board. On the under- side of the A4987 package is an exposed pad, which ...
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A4987 C3 GND U1 C4 GND C5 ROSC C1 GND GND GND VDD DMOS Dual Full-Bridge PWM Motor Driver With Overcurrent Protection OUT2B C6 GND OUT2A R4 R5 OUT1A GND OUT1B BULK GND CAPACITANCE C2 VBB LP package typical application ...
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A4987 VDD VBB 8 V GND GND V BB VREG SENSE 10 V GND DMOS Dual Full-Bridge PWM Motor Driver Pin Circuit Diagrams GND PGND GND IN01 IN02 IN11 IN12 V REG PH1 PH2 DMOS VREF Parasitic ...
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A4987 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 5. Step Sequencing for Full-Step Increments. DMOS Dual Full-Bridge PWM Motor Driver With ...
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A4987 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 ...
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A4987 OUT2B 1 PH2 2 GND 3 CP1 4 CP2 5 VCP 6 Terminal List Table Name CP1 CP2 PH1 PH2 GND IN02 IN12 NC OUT1A OUT1B OUT2A OUT2B REF IN11 ROSC SENSE1 SENSE2 ¯ S ¯ ¯ L ¯ ...
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A4987 ES Package, 24-Pin QFN with Exposed Thermal Pad 4.00 ±0. 25X 0.08 C +0.05 0.25 –0.07 0.50 BSC 0.45 MAX 2.70 DMOS Dual Full-Bridge PWM Motor Driver With Overcurrent Protection 4.00 ...
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A4987 LP Package, 24-Pin TSSOP with Exposed Thermal Pad 7.80 ±0. 4.32±0.05 24X 0.10 C +0.05 0.25 0.65 –0.06 DMOS Dual Full-Bridge PWM Motor Driver With Overcurrent Protection 4° ±4 0.15 3.00±0.05 4.40 ±0.10 6.40 ...
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A4987 Revision History Revision Rev. 1 Copyright ©2009-2011, Allegro MicroSystems, Inc. Allegro MicroSystems, Inc. reserves the right to make, from time to time, such de par tures from the detail spec tions as may be required to ...