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A1444 and A1445 Low-Voltage Full-Bridge Brushless DC Motor Driver with Hall Commutation, Externally Controlled Speed Regulation, Soft Switching, and Reverse Battery, Short Circuit, and Thermal Shutdown Protection

A1444 and A1445 Low-Voltage Full-Bridge Brushless DC Motor Driver with Hall Commutation, Externally Controlled Speed Regulation, Soft Switching, and Reverse Battery, Short Circuit, and Thermal Shutdown Protection
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Catalog excerpts

VDD Reverse Battery Output Full Bridge Q1Q3Q2Q4 SLEEP Power and SleepMode Control Active BrakingControl Drive LogicandSoft SwitchingControl GND VOUT1 Stall Detection 0.1 F VOUT2 AmHallElementp M Thermal ShutdownProtection PDC > ESD PWMControl >

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CharacteristicsSymbolTest ConditionsMin.Typ. > 1 Max.Unit Supply Voltage V > DD T > J < T > J (max) 2.0 4.2 V Extended Supply Voltage > 2 V > DDE T > J < T > J (max) 1.8 ֖4.2 V Supply Current I > IN >V > INHI , T > A = 25C, no load Ж4 6 mA V > DD(ON) V > IN < V > INLO , T > A = 25C Ж10 A Total Output On-Resistance I > OUT = 50 mA, V > DD = 2 V, T > A = 25ְC 3.9 ֖I > 3 R > DS(on) OUT = 50 mA, V > DD = 3 V, T > A = 25C Ж2.6 I > OUT = 50 mA, V > DD = 4 V, T > A = 25ְC 2.2 ֖ Reverse Battery CurrentI V > RDD = 4.2 V, current flowing out of VDD pin, T > RDD A = 25ְC ֖10 mA ֯S ϯL ϯE ϯE ϯP Input...

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CharacteristicsSymbolTest ConditionsMin.Typ. > 1 Max.Unit > OP 2 V V > DD 4 V35 75 G B Magnetic SwitchpointsB > RP 2 V V > DD 4 V֖75 35 ֖G B > HYS 2 V V > DD 4 V70 ֖G Output Polarity VOUT1B < B > RP LOW֖VB > B > OP HIGH֖VVOUT2B < B > RP HIGH ֖VB > B > OP LOW֖V > 1 Typical data are for initial design estimations only, and assume optimum manufacturing and application conditions, such as T > A = 25C. Performance may vary for individual units, within the specified maximum and minimum limits. > 2 Device operates with lower supply voltages, down to 1.8 V, with slight variation in specification of...

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Device Start-up The start-up behavior of the device output is determined by the applied magnetic field, as specified in the Electrical Characteris- tics table. Speed Control > When the rate of rotation exceeds the specified threshold, S > Antistall Algorithm Soft Switching Braking and Sleep Mode If a stall condition occurs, the device will execute an antistall algorithm to restart the motor. The A1444 and A1445 devices include a soft switching algorithm that controls the output switching slew rate for both output pins. As a result, the devices are ideal for use in applications requiring low...

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Allegro MicroSystems, Inc.115 Northeast CutoffWorcester, Massachusetts 01615-0036 U.S.A.1.508.853.5000; www.allegromicro.com >

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The device must be operated below the maximum junction tem-perature of the device, T > J (max). Under certain combinations of peak conditions, reliable operation may require derating supplied power or improving the heat dissipation properties of the appli- cation. This section presents a procedure for correlating factors affecting operating T > A = 25C, V > DD = 3 V, I > DD = 85 mA, V > LOAD = 2.43 V, I > LOAD = 83 mA, and R > JA = 250 аC/W, then: P > J . (Thermal data is also available on the Allegro MicroSystems website.)The package thermal resistance, R > D = V > DD I > DD ז V > LOAD I >...

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