Texas Instruments three-phase brushless DC gate driver

The Texas Instruments MCT8329A Three-phase brush grid driver provides a single-chip, code-free sensorless ladder solution for applications requiring high operating speeds or very fast startup times. And integrates a number of protection features to protect equipment, motors and systems from failure events. The device provides three half-gate drivers, each capable of driving both high - and low-side n-channel power MosFeTs.

The device uses an internal charge pump to generate the correct grid drive voltage and a bootstrap-up circuit to enhance the high-side mosFeTs. Drip charge pump includes support for 100% duty cycle. The grid drive architecture supports peak grid drive currents up to 1a source and 2a sinks. The McT8329a supports a single power supply with a wide input range of 4.5v to 60v.

Sensorless ladder control is highly configurable by setting registers in the non-volatile eepm (MCT8329A1I), ranging from motor startup behavior to closed-loop operation, which allows the device to operate independently once the configuration is complete. Motor current sensing uses an integrated current sensing amplifier to support a single external shunt resistor. The device receives speed commands via pwm input, analog voltage, variable-frequency square wave or i2c command.

Features

● Three-phase BLDC gate driver with integrated sensorless motor control algorithm
-   Code-free high-speed Trapezoidal Control
-   Supports up to 3kHz (electrical frequency)
-   Very fast startup time (< 50ms)
-   Fast deceleration (< 150ms)
-   Supports 120° or 150° modulation to improve acoustic performance
-   Forward and reverse windmilling support
-   Analog, PWM, freq., or I2C-based control input
-   Configurable motor startup and stop options
-   Optional closed-loop speed or power control, open-loop voltage control
-   5-point configurable reference profile support
-   Anti-voltage surge prevents overvoltage
-   Variable monitoring through DACOUT
● 65V three-phase half-bridge gate driver
-   Drives three high-side and three low-side N-Channel MOSFETs, 4.5V to 60V operating voltage
-   Supports 100% PWM duty cycle
-   Bootstrap-based gate driver architecture
-   1A/2A maximum peak source/sink current
● Integrated current sense amplifier
-   Adjustable gain (5V/V, 10V/V, 20V/V, 40V/V)
● Low-power sleep mode
-   5µA (maximum) at VPVDD = 24V, TA = 25°C
● Speed loop accuracy of < 3% with internal clock
● Supports up to 100kHz PWM frequency
● Accurate LDO (AVDD) 3.3V ±3%, 50mA support with AVDD connected to VREG
● Independent driver shutdown path (DRVOFF)
● Spread spectrum for EMI mitigation
● Suite of Integrated protection features
-   Supply undervoltage lockout (UVLO)
-   Motor lock detection (3 different types)
-   Overcurrent protection (OCP)
-   Thermal shutdown (TSD)
-   Fault condition indication pin (nFAULT)
-   Optional fault diagnostics over the I2C interface

Applications

● Brushless-DC (BLDC) motor modules LDO out
● Cordless vacuum cleaners PWM, analog, frequency, or commanded over I2C
● HVAC blowers and ventilators
● Appliance fans and pumps
● Cordless garden and power tools, lawnmowers