A3957SLB Allegro, A3957SLB Datasheet
A3957SLB
Specifications of A3957SLB
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A3957SLB Summary of contents
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... Logic/Reference Input Voltage Range -0 0 Sense Voltage Package Power Dissipation ( C A3957SA . . . . . . . . . . . . . . . . 2.08 W† A3957SLB . . . . . . . . . . . . . . . 2.23 W† Operating Temperature Range -20˚C to +85˚C A Junction Temperature +150˚C J Storage Temperature Range -55˚C to +150˚ Output current rating may be limited by duty cycle, ambient temperature, and heat sinking. ...
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... FULL-BRIDGE PWM MICROSTEPPING MOTOR DRIVER FUNCTIONAL BLOCK DIAGRAM (A3957SLB shown) PHASE 10 GROUND 6 7 UVLO & TSD 18 19 MIXED-DECAY COMPARATOR PFD 2 + – BLANKING V CC A3957SA NO 16 GROUND 1 NC CONNECT 2 SENSE OUT OUT A LOGIC LOAD SUPPLY V BB PFD REF 11 PHASE 6 LOGIC SUPPLY ...
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FULL-BRIDGE PWM MICROSTEPPING MOTOR DRIVER 1 2 where V Table 1 — PHASE Truth Table PHASE OUT ...
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FULL-BRIDGE PWM MICROSTEPPING MOTOR DRIVER ELECTRICAL CHARACTERISTICS at T otherwise noted.) Characteristic Symbol Power Outputs Load Supply Voltage Range Output Leakage Current Output Saturation Voltage V (Forward or Reverse Mode) Sense Current Offset Clamp Diode Forward Volt. (Sink or ...
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FULL-BRIDGE PWM MICROSTEPPING MOTOR DRIVER ELECTRICAL CHARACTERISTICS at T otherwise noted.) Characteristic Control Circuitry (continued) Mixed-Decay Comparator Trip Points Mixed-Decay Comparator Input Offset Voltage Mixed-Decay Comparator Hysteresis Reference Input Current Reference Divider Ratio Digital-to-Analog Converter Accuracy* Current-Sense Comparator Input ...
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FULL-BRIDGE PWM MICROSTEPPING MOTOR DRIVER ELECTRICAL CHARACTERISTICS at T otherwise noted.) Characteristic Symbol AC Timing PWM RC Fixed Off-time t PWM Turn-Off Time t PWM(OFF) PWM Turn-On Time t PWM(ON) PWM Minimum On Time t Crossover Dead Time = ...
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FULL-BRIDGE PWM MICROSTEPPING MOTOR DRIVER Source Driver Saturation Voltage 1.5 1.25 1.0 0.75 0.5 0. 0.5 0.75 0.25 OUTPUT CURRENT IN AMPERES Clamp Diode Forward Voltage 1.5 1.25 1.0 0.75 0.5 0. 0.5 0.75 0.25 ...
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... FULL-BRIDGE PWM MICROSTEPPING MOTOR DRIVER A3957SA A3957SLB Terminal Pin Lead Name – PFD 6 3 REF – 6-7 GROUND LOGIC SUPPLY 11 10 PHASE – – OUT – SENSE 16 – 18-19 GROUND – OUT 4 23 LOAD SUPPLY – For the ‘A’ package, pins 1 and 8 must be externally connected together. ...
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FULL-BRIDGE PWM MICROSTEPPING MOTOR DRIVER Functional Description Two A3957S— full-bridge PWM microstepping motor drivers are needed to drive the windings of a bipolar stepper motor. Internal pulse-width modulated (PWM) control circuitry regulates each motor winding’s current. The peak motor ...
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FULL-BRIDGE PWM MICROSTEPPING MOTOR DRIVER Under some circumstances slow-decay mode PWM can fail to maintain good current regulation: 1) The load current will fail to regulate in slow-decay mode due to a sufficiently negative back-EMF voltage in con- junction ...
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FULL-BRIDGE PWM MICROSTEPPING MOTOR DRIVER cost of decreased average current accuracy or increased driver and motor losses. Mixed Current-Decay Mode PFD 2.9 V, the device will mixed current-decay mode. Mixed-decay mode allows the user ...
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... The output transistors are re-enabled when the junction temperature cools to approximately +150 C. Stepper Motor Applications. The A3957SB or A3957SLB are used to optimize performance in microstepping/sinusoidal BRIDGE A 1 ...
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FULL-BRIDGE PWM MICROSTEPPING MOTOR DRIVER Full / / / / Step Step Step Step Step PHASE ...
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FULL-BRIDGE PWM MICROSTEPPING MOTOR DRIVER 16 0.280 0.240 1 0.070 0.045 0.210 MAX 0.015 MIN 0.022 0.014 16 7.11 6.10 1 1.77 1.15 5.33 MAX 0.39 MIN 0.558 0.356 NOTES:1. Exact body and lead configuration at vendor’s option within ...
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... NOTES:1. Exact body and lead configuration at vendor’s option within limits shown. 2. Lead spacing tolerance is non-cumulative 3. Webbed lead frame. Leads 4, 5, 12, and 13 are internally one piece. A3957SLB Dimensions in Inches (for reference only 0.050 0.6141 BSC ...
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... The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use; nor for any infringe- ments of patents or other rights of third parties which may result from its use. 115 Northeast Cutoff, Box 15036 ...