A3977SED-T Allegro Microsystems Inc, A3977SED-T Datasheet
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A3977SED-T
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A3977SED-T Summary of contents
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Microstepping DMOS Driver with Translator Features and Benefits ▪ ±2 output rating ▪ Low r outputs, 0.45 Ω source, 0.36 Ω sink typical DS(on) ▪ Automatic current decay mode detection/selection ▪ 3.0 to 5.5 V logic supply ...
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... A3977 Selection Guide Part Number Packing A3977KEDTR-T 450 per reel A3977SEDTR-T 450 per reel A3977SLPTR-T 4000 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 ...
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A3977 LOGIC SUPPLY UVLO VDD AND FAULT REF. SUPPLY REF DAC RC1 4 STEP DIR RESET HOME SLEEP SR V PFD ENABLE PFD DAC Microstepping DMOS Driver with Translator FUNCTIONAL BLOCK DIAGRAM VREG ...
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A3977 LP Pin-out (TSSOP) Microstepping DMOS Driver with Translator Table 1. Microstep Resolution Truth Table MS MS Resolution Full step (2 phase Half step L H Quarter step H H Eighth step 4 Allegro ...
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A3977 ELECTRICAL CHARACTERISTICS Characteristic Output Drivers Load Supply Voltage Range Output Leakage Current Output On Resistance Body Diode Forward Voltage Motor Supply Current Control Logic Logic Supply Voltage Range Logic Input Voltage Logic Input Current Maximum STEP ...
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A3977 ELECTRICAL CHARACTERISTICS Characteristic Output Drivers (continued) Thermal Shutdown Temp. Thermal Shutdown Hysteresis UVLO Enable Threshold UVLO Hysteresis Logic Supply Current * Operation at a step frequency greater than the specifi ed minimum value is possible but not warranteed. NOTES: ...
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A3977 Device Operation. The A3977 is a complete microstep- ping motor driver with built in translator for easy operation with minimal control lines designed to operate bipolar stepper motors in full-, half-, quarter- and eighth-step modes. The current ...
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A3977 Fixed Off-Time. The internal PWM current-control circuitry uses a one shot to control the time the drivers remain off. The one shot off-time, t the selection of an external resistor (R connected from the RC timing terminal to ground. ...
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A3977 Synchronous Rectifi cation. When a PWM off-cycle is triggered by an internal fi xed off-time cycle, load current will recirculate according to the decay mode selected by the control logic. The A3977 synchronous rectifi cation fea- ture will turn ...
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A3977 Layout. The printed wiring board should use a heavy ground plane. For optimum electrical and thermal performance, the driver should be soldered directly onto the board. The load supply terminal with an electrolytic capacitor (>47 μF is ...
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A3977 Full Half Step # Step # Home state; HOME output low. Microstepping DMOS Driver with Translator Table 2. Step Sequencing (DIR = L) Phase 2 Quarter ...
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A3977 Microstepping DMOS Driver with Translator Full-Step Operation DIR = The vector addition of the output currents at any step is 100%. 12 Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 ...
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A3977 Microstepping DMOS Driver with Translator Half-Step Operation DIR = The mixed-decay mode is controlled by the percent fast decay voltage (V greater than 0.6V the voltage on the PFD input ...
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A3977 Microstepping DMOS Driver with Translator Quarter-Step Operation DIR = The mixed-decay mode is controlled by the percent fast decay voltage (V greater than 0.6V the voltage on the PFD input ...
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A3977 Microstepping DMOS Driver with Translator 8 Microstep/Step Operation DIR = The mixed-decay mode is controlled by the percent fast decay voltage (V greater than 0.6V the voltage on the PFD input ...
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A3977 Terminal Name Terminal Description GND Analog and power ground SENSE Sense resistor for bridge 1 1 HOME Logic output DIR Logic Input OUT DMOS H bridge 1 output (internal) connection PFD Mixed decay setting RC ...
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A3977 16.59 ±0.08 17.53 ±0.13 44X 0.10 Microstepping DMOS Driver with Translator ED Package, 44-pin PLCC 17.53 ±0.13 16.59 ±0. 0.74 ±0.08 C 0.43 ±0.10 7.75 ±0.36 7.75 ±0.36 For Reference Only (reference JEDEC MS-018 AC) ...
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A3977 9.70 ±0. 5.00 28X 0.10 C +0.05 0.25 0.65 –0.06 Copyright ©2002-2010, Allegro MicroSystems, Inc. Allegro MicroSystems, Inc. reserves the right to make, from time to time, such de par tures from the detail ...