A3941KLPTR-T Allegro Microsystems Inc, A3941KLPTR-T Datasheet
A3941KLPTR-T
Specifications of A3941KLPTR-T
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A3941KLPTR-T Summary of contents
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Features and Benefits ▪ High current gate drive for N-channel MOSFET full bridge ▪ High-side or low-side PWM switching ▪ Charge pump for low supply voltage operation ▪ Top-off charge pump for 100% PWM ▪ Cross-conduction protection with adjustable dead ...
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... A3941 Selection Guide Part Number A3941KLPTR-T 4000 pieces per reel Absolute Maximum Ratings* Characteristic Load Supply Voltage Logic Inputs and Outputs V5 Pin LSS Pin VDSTH Pin SA and SB Pins VDRAIN Pin GHA and GHB Pins GLA and GLB Pins CA and CB Pins Operating Temperature Range ...
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A3941 VBB V5 +5V Reg FF1 FF2 Diagnostics and Protection VDSTH PWMH PWML Control Logic PHASE SR RESET RDEAD Automotive Full Bridge MOSFET Driver Functional Block Diagram C P CP2 CP1 Charge Pump Regulator Charge Bootstrap Pump Monitor High Side ...
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A3941 ELECTRICAL CHARACTERISTICS valid at T Characteristics Supply and Reference Load Supply Voltage Functional 1 Operating Range Load Supply Quiescent Current VREG Output Voltage V5 Output Voltage V5 Line Regulation V5 Load Regulation V5 Short-Circuit Current Bootstrap Diode Forward Voltage ...
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A3941 ELECTRICAL CHARACTERISTICS (continued) valid at T Characteristics Logic Inputs and Outputs FF1 and FF2 Fault Output (Open Drain) FF1 and FF2 Fault Output Leakage Current RDEAD Current 3 Input Low Voltage Input High Voltage Input Hysteresis (Except RESET Pin) ...
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A3941 Gate Drive Timing – PWM inputs, Slow Decay, Synchronous Rectification PWMH t P(off) GHx GLx SR=1, PWML=1 Gate Drive Timing – PWM inputs, Slow Decay, Diode Rectification PWMH t P(off) GHx GLx SR=0, PWML=1 Gate Drive Timing – Phase ...
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A3941 The A3941 is a full-bridge MOSFET driver (pre-driver) requiring a single unregulated supply includes an integrated 5 V logic supply regulator. The four high current gate drives are capable of driving a wide ...
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A3941 In some applications a safety resistor is added between the gate and source of each FET in the bridge. When a high-side FET is held in the on-state, the current through the associated high-side gate-source resistor ( ...
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A3941 Table 1. Phase Control Truth Table Inputs PWMH PWML PHASE ...
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A3941 pins), synchronous rectification turns on the MOSFET that is complementary to the one that is turned off. This ensures that the current passes through the lower resistance MOSFET rather than the diode. When SR is low, synchronous rectification is ...
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A3941 the event that two or more faults are detected simultaneously, the state of the fault flags will be determined by a logical OR of the flag states for all detected faults. Table 3. Fault Definitions Flag State Fault Description ...
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A3941 tions, the output from the comparators are ignored under two conditions: ▪ while the external FET is off, and ▪ until the end of the period, referred to as the fault blank time, after the FET is turned on. ...
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A3941 Power Bridge Management Using PWM Control The A3941 provides two PWM control signals, a phase control for current direction, and the ability to enable or disable syn- chronous rectification. This allows a wide variety of full bridge control schemes ...
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A3941 schemes, the PHASE input is still required to reverse the load current. Although fast decay with diode rectification provides a higher degree of current control than slow decay schemes, it still may not provide sufficient control for servo systems ...
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A3941 For R values between 3 kΩ and 240 kΩ, at 25°C the nomi- DEAD nal value can be approximated by: DEAD (nom DEAD 1.2 + (200 / R where R is ...
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A3941 voltage of the Zener diodes between the Cx and Sx pins. In most applications, with a good ceramic capacitor the working voltage can be limited Bootstrap Charging It is good practice to ensure the high-side bootstrap ...
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A3941 [( – CPUMP BB REG – REG AV × V × N × SWITCHING GATE REG PWM where: × ...
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A3941 Quiet Ground Controller Supply Ground Figure 4. Supply routing suggestions Input and Output Structures VBB (A) Gate drive outputs ESD 3 kΩ PWMx SR PHASE 8.5 V (E) Logic inputs, no ...
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A3941 Terminal List Number Name 1 VDRAIN High-side common drain 2 LSS Low-side common source 3 GLB Low-side gate drive Load connection B 5 GHB High-side gate drive Bootstrap capacitor B 7 VREG Regulated ...
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A3941 Package LP 28-Pin TSSOP with Exposed Thermal Pad 9.70 ±0. 5.00 28X 0.10 C +0.05 0.25 0.65 –0.06 Copyright ©2008-2010, Allegro MicroSystems, Inc. The products described here are manufactured under one or more U.S. ...