A3938SEQ Allegro Microsystems Inc, A3938SEQ Datasheet
A3938SEQ
Specifications of A3938SEQ
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A3938SEQ Summary of contents
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Features and Benefits ▪ Drives a wide range of N-channel MOSFETs ▪ Low-side synchronous rectification ▪ Power MOSFET protection ▪ Adjustable dead time for cross-conduction protection ▪ Selectable coast or dynamic brake on power-down or RESET input ▪ Fast/slow current ...
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A3938 Selection Guide Part Number Packing A3938SLDTR-T 4000 per reel Absolute Maximum Ratings Characteristic Load Supply Voltage VREG Pin, Transient Logic Input Voltage Range Sense Voltage Range Output Voltage Range SA, SB, SC Pins GHA, GHB, GHC Pins CA, CB, ...
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A3938 FAULT O.D. LCAP + 0 PWM Control Logic DIR RESET BRAKE MODE RC RC Blanking Fixed Off-Time REF DEAD Dead-Time Adjust AGND A For 12 V applications, VBB must be shorted ...
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A3938 ELECTRICAL CHARACTERISTICS μF, PWM = 22.5 kHz, square wave, two phases active VREG Characteristics Quiescent Current LCAP Regulator VREG =VBB Supply Voltage Range VREG Output Voltage VREG Load Regulation VREG Line Regulation Control Logic Logic Input ...
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A3938 ELECTRICAL CHARACTERISTICS C = 0.1 μ μF, PWM = 22.5 kHz, square wave, two phases active BOOT VREG Characteristics Bootstrap Capacitor Bootstrap Capacitor Voltage Bootstrap R OUT Charge Current (Source) Current Limit Circuitry Input Offset Voltage ...
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A3938 A logic input that enables the device. Has internal RESET. 50 kΩ pull-up to LCAP. Setting RESET to 1 coasts or brakes the motor, depending on the state of the BRKSEL pin. Set- ting RESET to 0 enables the ...
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A3938 Motor power supply connection for the A3938 and VBB. for power MOSFETs good practice to connect a decou- pling capacitor from this pin to AGND, as close to the device pins as possible. Analog input to current ...
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A3938 Synchronous Rectifi cation. sumption in the external MOSFETs, during the load current recirculation PWM-off cycle, the A3938 control logic turns on the appropriate low-side driver only. The reverse body diode of the power MOSFET conducts only during the dead ...
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A3938 each commutation stalled motor results from a fault, the fault can only be cleared by toggling the RESET pin power-up sequence. Load current can be regulated by Current Regulation. an internal fi xed off-time, ...
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A3938 Terminal List Name PGND RESET GLC SC GHC CC GLB SB GHB CB GLA SA GHA CA VREG LCAP FAULT MODE VBB DIR BRAKE BRKCAP BRKSEL PWM RC SENSE REF DEAD AGND N/C Three-Phase Power MOSFET ...
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A3938 9.70 ±0. 38X 0.10 C 0.22 ±0.05 0.50 Copyright ©2003-2008, 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 right ...