Texas Instruments Debuts Three Phase Brushless DC Motor Gate Driver Unit

The DRV325x-Q1 group of MOSFET gate driver units (GDU) provide 3.5 and 4.5 amp peak source and sink gate drive currents, respectively, enabling the unit to shorten the rise and fall times of the VDS of the MOSFET(s) being driven. The units are optimized for 48-volt applications and feature a 90 volt MOSFET operating voltage range

Simplified schematic for the DRV325x-Q1. At present only the DRV3255 is active and ready for new designs. Image courtesy of Texas Instruments.

The DRV3255-Q1 is claimed by Texas Instruments (TI) to be the industry’s first 3-phase half-bridge BLDC motor driver that incorporates both high-side and low-side active short circuit logic. Designed for 48-volt power systems, it protects against switching transients ranging up to 95 volts. It supports hybrid vehicles with electric motor powers of up to 30 kilowatts.. At the same time, the unit’s high level of integration will serve to eliminate what TI estimates to be between 12 to 24 passive components.

 

TI’s Purpose

The DRV3255 is aimed largely at what the company describes as mild hybrid electric vehicles (MHEVs). These hybrid vehicles employ 48-V motor-drive systems aimed at taking some of the load off the vehicle’s internal combustion engine, serving to reduce environmentally harmful emissions.

 

Image courtesy of Texas Instruments.
 

As per Asif Anwar, director of the powertrain, body, chassis and safety service at Strategy Analytics, “A 48-V system is a step-change that original equipment manufacturers [OEMs] can implement to meet goals around reducing emissions, while also adding power for advanced driver-assistance system features and managing power-hungry loads such as the heating, ventilation and air conditioning system.” He goes on to state that “Combining leading-edge performance characteristics with functional safety and Grade 0 translates to real-world, system-level operational benefits that will help OEMs achieve these goals.”

 

Important Features

Configurable active short circuit (ASC) function for both high-side and low-side. The device communicates via SPI bus, and it supports both 3.3 and 5-volt logic inputs.

Specific Protection Features Include:

• Monitors for MOSFET V(DS) and for R(SHUNT) over-current
• Battery voltage monitored
• MOSFET V(GS) gate faults
• Analog self-test
• Thermal shut down
• Indicator pins provided for notifying of faults

Applications

• Hybrid Vehicle electric motors
• eTurbos and eBoosters
• Transmission control and actuation
• HVAC systems
• Electrical power steering
• Oil, transmission, and water pumps 

 

Physical

• The unit is available in a 10 x 10 mm, 64 pin HTQFP package
• The temperature range is from -40 to +150℃

 

Image courtesy of Texas Instruments.

 

Regulatory and Safety Concerns

• HBM (human body model)  ESD classification level 2
• CDM (charge device model) ESD classification level C4B
• AEC Q-100 Grade 0
• ASIL (automotive safety integrity level) is targeted

 

Image courtesy of Texas Instruments.

Getting to Market Faster

TI often offers evaluation modules to aid engineers in the process of familiarizing themselves with new models. This appears to be the case with the DRV325-Q1EVM.