A4935KJPTR-T Allegro Microsystems Inc, A4935KJPTR-T Datasheet
A4935KJPTR-T
Specifications of A4935KJPTR-T
A4935KJPTR-T
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A4935KJPTR-T Summary of contents
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Features and Benefits ▪ High current 3-phase gate drive for N-channel MOSFETs ▪ Cross-conduction protection with adjustable dead time ▪ Top-off charge pump for 100% PWM ▪ Charge pump for low supply voltage operation ▪ Uncommitted current sense amplifier ▪ ...
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... They can be configured to protect the power FETs under most short circuit conditions. Detailed diagnostics are available as a serial data word. Selection Guide Part Number A4935KJPTR-T 1500 pieces per reel Absolute Maximum Ratings* Characteristic Load Supply Voltage ...
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A4935 VBB Logic VDD Supply COAST PWMH PWML AHI Control ALO Logic BHI BLO CHI CLO CCEN RESET RDEAD Diagnostics and Protection ESF Short to Supply FF1 FF2 VDSTH Automotive 3-Phase MOSFET Driver Functional Block Diagram C P CP1 CP2 ...
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A4935 ELECTRICAL CHARACTERISTICS valid at T Characteristics Supply and Reference Load Supply Voltage Functional Operating Range 1 Load Supply Quiescent Current Logic Supply Voltage Logic Supply Quiescent Current VREG Output Voltage Bootstrap Diode Forward Voltage Bootstrap Diode Resistance Bootstrap Diode ...
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A4935 ELECTRICAL CHARACTERISTICS (continued) valid at T unless noted otherwise Characteristics Dead Time 2 Logic Inputs and Outputs FF1 and FF2 Fault Output FF1 and FF2 Fault Output Leakage Current RDEAD Input Low Voltage RDEAD Current 3 Input Low Voltage ...
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A4935 ELECTRICAL CHARACTERISTICS (continued) valid at T unless noted otherwise Characteristics Small Signal –3 dB Frequency Bandwidth Settling Time Output Dynamic Range Output Current Sink Output Current Source VREG Supply Ripple Rejection DC Common Mode Rejection AC Common Mode Rejection ...
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A4935 xHI xLO t DEAD GHx GLx t P(off) Synchronous Rectification PWMH t P(off) GHx GLx t DEAD xHI = 1, xLO = 0, PWML = 1 COAST t P(off) GHx GLx xHI = 1, xLO = 0, PWMH = ...
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A4935 The A4935 is a three-phase MOSFET driver (pre-driver) with separate supplies for the logic, and for the analog and drive sec- tions. This permits operation with a regulated logic supply from 3 to 5.5 V and with an unregulated ...
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A4935 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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A4935 • Setting PWML low turns off active low-side drives and turns on the complementary high-side drives. This provides low-side– chopped slow-decay PWM with synchronous rectification. • PWMH and PWML may also be connected together and driven with a single ...
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A4935 Current Sense Amplifier An uncommitted differential sense amplifier is provided to allow the use of either low value sense resistors or a current shunt as the current sensing element. The input common mode range, CMR, allows the below-ground current ...
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A4935 switching. Any short faults detected will always be latched in the fault register. When a short or undervoltage fault is present, a clock can be applied to FF2 and detailed fault information can be read from FF1 as a ...
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A4935 the output from the comparators are ignored under two condi- tions: ▪ 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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A4935 Fault Register All undervoltage and short faults are recorded in a 10-bit fault register as defined in table 3. The fault register accumulates all detected faults until cleared by setting RESET low, by cycling the power off and on, ...
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A4935 FF2 FF1 V fault detected FF2 pulled up by resistor DS FF2 AH FF1 UV fault detected FF1 and FF2 pulled up by resistor FF2 AH FF1 Figure 1. Fault flag sequence diagrams Automotive 3-Phase MOSFET Driver Overtemperature Condition ...
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A4935 Power Bridge Management Using PWM Control The A4935 provides individual high-side and low-side controls for each phase, plus two PWM control signals and a coast con- trol. This allows a wide variety of 3-phase bridge control schemes to be ...
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A4935 with either 2-phase or 3-phase excitation. When using fast decay, a PWM duty cycle of 50% results in zero effective motor torque. A duty cycle of less than 50% causes negative effective torque, and greater than 50% causes positive ...
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A4935 is set to zero by connecting RDEAD to AGND, the fault blank time typically defaults to 2 μs. Cross-Conduction In some circumstances it is desirable to allow activation of both high-side and low-side FETs in a single phase of ...
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A4935 tor (>1000 nF). If the bootstrap capacitor voltage does not reach the threshold within approximately 200 μs, an undervoltage fault will be flagged. VREG Capacitor Selection The internal reference, VREG, supplies current for the low-side gate drive circuits and ...
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A4935 The A4935 can also be used to perform regenerative braking. This is equivalent to reversing the motor commutation sequence or using fast decay with synchronous rectification. Note that phase commutation must continue for regenerative braking to operate and the ...
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A4935 • Sensitive connections such as RDEAD and VDSTH, which have very little ground current, should be connected to the Quiet ground (refer to figure 5), which is connected independently, closest to the AGND pin. These sensitive components should never ...
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A4935 Input and Output Structures (A) Gate drive outputs ESD COAST 3 kΩ ESF PWMx xHI xLO 8.5 V (E) Logic inputs, no pulldown VREG ESD ...
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A4935 Terminal List Pin Pin Name 1, 24, 25, 35 internal connection; connect to AGND 36, 37 RESET Standby mode control 3 ESF Enable Stop on Fault input 4 FF2 Fault Flag 2 and serial clock ...
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A4935 Package JP 48-Pin LQFP with Exposed Thermal Pad 9.00 ±0.20 7.00 ±0.20 B 9.00 ±0.20 7.00 ±0. 5.00±0.04 48X 0.08 C 0.22 ±0.05 0.50 Copyright ©2007-2010, Allegro MicroSystems, Inc. The products described here are manufactured ...