The A4935 is an N-channel external power MOSFETThree-phase controller, which is specifically targeted at automotive applications.
The unique charge pump regulator provides a complete (>10 V) gate driver to handle battery voltages as low as 7 V and allows the A4935 to be usedGate driversOperates when the voltage drops to 5.5 V.
The bootstrap capacitor is used to provide the above battery supply voltage required for the N-channel MOSFET. The high-side drive internal charge pump allows DC (100% duty cycle) operation.
The device provides full control of all six power FETs in a three-phase bridge, allowing the motor to be driven by block rectification or sinusoidal excitation. Integrated crossover control and resistor-adjustable inductive time save the power FET from breakdown.
The bridge current can be measured using an integrated current sense amplifier. This is an unconstrained difference amplifier with a ground-ground common-mode mode range, allowing it to be used in low-side current sensing applications. The gain and offset are defined by external resistors.
Integrated diagnostics provide undervoltage, overtemperature, and power bridge faults. They can be configured to protect the power FETs in most short-circuit conditions. Detailed diagnostics are available in the form of serial data words.
The A4935 is available in a 48-pin LQFP package with exposed heat shield (suffix JP). This is a footprint (81 mm2Smaller power package. The packages are lead (Pb) free, and the leadframes are 100% matte tin.
- High-current 3-phase gate driver for N-channel MOSFETs
- Cross-conduction protection with adjustable inductive time
- The charge pump provides 100% PWM when fully charged
- The charge pump operates at low supply voltages
- Unconstrained current sense amplifier
- 5.5 to 50 V supply voltage range
- Compatible with 3.3 V and 5 V logic
- Comprehensive diagnostic output
- Low current sleep mode