Three-phase smart gate driver has three current shunt amplifiers

The Texas Instruments DRV8304 device is an integrated gate driver for three-phase brushless DC (BLDC) motors applications for 12V and 24V DC rails. These applications include FOC, sinusoidal current control, and trapezoidal current control of BLDC motors. The device combines three CSA for sensing the phase currents of these motors for optimum FOC and current-control system implementation. An AUTOCAL option automatically calibrates the CSA offset error for precise current sensing. The device is based on SGD architecture to remove the requirement of any external gate components (resistors and Zener diodes) while completely protecting the external FETs. The SGD architecture optimises dead time to evade any shoot-through conditions, gives flexibility in reducing EMI by gate slew-rate control, and guards against any gate-short conditions through VGS hand-shaking and dead time insertion. Strong pulldown current also stops any DV/DT gate turnon. Various PWM control modes (1x, 3x, 6x, and independent) are provided for easy interfacing to control circuits that can be run by the 30mA, 3.3V internal regulator. These modes reduce the number of output peripherals of the controller for the particular motor-control needs and give flexibility of control. The device also provides a 1x mode for sensored trapezoidal control of the BLDC motor by utilising the internal block-commutation table. Also, the device can be configured to run multiple loads, such as solenoids in independent mode.