Even before electric vehicles started to enter the market, the number of electric motors integrated into the vehicle were significant. The most obvious application is fans, used both to cool the engine and to keep passenger and driver cool or warm as the season determines. Air conditioning systems have several motors to control the flaps, coupled with a control system that provide a comfortable environment. And, so we don’t lose that nice environment by opening the electric windows, the side mirrors can be set as required by motors too.
As we are all too aware, vehicles have to withstand some harsh environments, working as expected in the heat of the outback or dessert, as well as in the depths of winter at sub-zero temperatures. Not only that, the solutions must be reliable, providing service over the lifetime of the vehicle. The electrical environment in the vehicle is also tough and challenging. Voltage spikes pass over power cables, while the supply can also drop significantly during cranking. Automotive engineers must also ensure that their solutions are both electromagnetically compatible with, and not impacted by, other in-vehicle systems.
Increasingly comfort functions demanding high levels of torque are moving from purely mechanical to electromechanical. This is already the case for sunroofs and windows, but also covers door-openers and tailgates. While windows and a sunroof will require around 12 Nm of torque, a tailgate can require torque in the 140 Nm range. Such solutions cannot impact on the vehicle’s design and often need to fit into an existing available space. This means a careful mechanical design is required together with a compact electronic control solution that is both robust and provides diagnostics for a body electronic control unit (ECU).
Many solutions focus on higher integration, coupling a microcontroller (MCU) with both drivers and MOSFETs. This has a certain elegance but can be challenging in an automotive market that is looking to reuse existing software as part of AUTOSAR. If the integrated microcontroller is not supported, the solution looks less attractive. If a solution already exists for functional safety compliant MCU, it can be preferable to just focus on upgrading the power stage to meet new application demands and requirements.
By integrating MOSFETs with a control device and drivers, the TB9111FTG offers itself as a perfect companion to upgrade the power stage of existing designs. This 3-in-1 system-in-package (SiP) features both an N- and P-channel FET with integrated diodes that are used for monitoring temperature. This provides minimal thermal lag. The switches support currents of up to 50 A, or short pulses that reach 100 A. The control chip provides a range of diagnostics for fault identification, such as under-voltage detection, current limit detection, and overcurrent shutdown. Dead time generation is also integrated. Several devices can also be combined to implement an H-bridge for DC motors, or for the control of brushless DC motors (BLDC).
If you are considering for a new automotive capable motor control solution, why not review our white paper on this topic here: