3 Phase Brushless Motor Driver using L6235

The project presented here is a 3-phase Brushless motor driver. The project consists of an L6235 device which is DMOS fully integrated 3-phase motor driver with overcurrent protection. Manufactured in BCD technology, the device combines isolated DMOS power transistors with CMOS and bipolar circuits on the same chip. The device includes all the circuitry needed to drive a 3-phase BLDC motor including a 3-phase DMOS bridge, a constant off-time PWM current controller, and the decoding logic for single-ended hall sensors that generates the required sequence for the power stage. Running the project in stand-alone mode, instead, three control pins enable the device, setting the direction of the rotation, breaking the motor, and the jumper chooses to run in torque or speed mode. The board is suitable for small motors used in many home appliances and can handle torque and speed control with a high efficiency of up to 95%.

Operation

• CN4: Pin2 High/Low to select the Direction of the Motor
• CN4: Pin 3 Enable, High=Enable, Low = Disable
• CN4: Pin 4 Brake, High=Normal Operation, Low=Brake
• J1: Jumper Speed Mode or Torque Mode Selection
• PR1: Adjust the Speed

Features

• Operating supply voltage from 8 to 48 V
• Load Current Up to 2.8A, Peak Current 5.6Amp
• Non-dissipative overcurrent detection and protection
• Diagnostic output
• Constant t_OFF PWM current controller
• Slow decay synchr. rectification
• 60° and 120° hall effect decoding logic
• Brake function
• Cross conduction protection
• Thermal shutdown
• Undervoltage lockout
• Integrated fast freewheeling diodes (Chip)
• 4 x 3mm Mounting Holes
• PCB Dimensions 59.69 x 49.53mm

Current Ratings

Load current rated for a maximum of 2.8A_RMS. and 5.6A_peak. The device has a built-in Over-Current Detection (OCD) that allows protection against short circuits between the outputs and between the output and ground.