Brushed DC motor drivers for functionally safe vehicle electrification

The drivers feature SPI interface for control versatility, enhanced thermal features for reliable continuous operation and Processor Expert analog software driver enablement for streamlined embedded system design. Additionally, the fully integrated drivers use NXP’s 45 V SmartMOS process. This process reduces board space by combining digital control, precision analogue circuitry and power MOSFETs in a small, thermally efficient, 8x8mm PQFNpackage.

“With growing demands for functional safety as the automotive industry moves toward self-driving vehicles, NXP has been in the forefront in developing solutions that meet international standards such as ISO26262,” said Jens Hinrichsen, Senior Vice President and General Manager of the advanced automotive analogue business line, NXP. “The HB2000 and HB2001 are the first motor drivers designed using ISO26262 processes in support of ASIL level C and D system qualification. NXP continues to assert itself as a leading expert in functional safety for enabling secure, connected, energy-efficient self-driving cars.”

In addition to functional safety, NXP’s analogue software driver enablement technology leverages processor expert source code generation to revolutionise mixed signal embedded system design. With this enablement support, the motor drivers appear as any other integrated peripheral within the MCU software development tools for MCU-savvy embedded system designers to quickly implement them in their software projects. Analogue software driver enablement for the HB2000 and HB2001 will be compatible with legacy processor expert tools as well as the integrated development environments (IDE) for Kinetis MCUs such as Kinetis Design Studio.

As part of vehicle electrification, automotive makers are addressing emissions and ADAS challenges by replacing belt-driven loads and hydraulic controls with small, reliable electric motors. As the number of motors and motor drivers in the car continues to grow, space considerations become increasingly important. The HB2000 and HB2001 delivers 5A rms, >10 A peak output current capability in a package that is 42% smaller than the equivalent market offerings available today. Also to maintain cool operation, the device provides 50% lower package thermal resistance and 50% lower RDS(_ON) at <65 mΏ, patented thermal protected current limiting and high-side current recirculation.

The automotive industry is actively cautious about functional safety. ISO26262 certification and ASIL level C/D qualification are now frequently considered a standard necessity. They require complete safety manuals and supporting documentation that outline system behavior for preventing malfunction. System safety integration is made much easier using solutions like the HB2000 and HB2001 that are designed using ISO26262 certified methodologies and include advanced diagnostic reporting and safety features.

The device senses load currents within ±5% tolerance across the entire operating range, without compromising output performance. This allows advanced system-level diagnostics and closed loop motor control. Customers have design flexibility with a choice of PQFN or SOIC-EP package and two RDS(_ON) options. Design configurability is available, through SPI control for different loads and EMI conditions, with four current limit and eight slew rate settings. Several different applications can be addressed with a single software platform saving development time and investment.

NXP offers a kit that includes the Kinetis KL-25Z Freedom microprocessor evaluation board with a plug-in HB2000 shield board and SPIGen user interface software for controlling a motor. The companion software driver embedded component for the Processor Expert and Kinetis Expert enablement tools will be available for download in late April.

Many NXP analog products meet critical industrial market requirements, including operation across extended temperature ranges. These products are designed and manufactured with rigorous process controls and qualified using industry standard methodologies designed to yield defect rates in line with the stringent requirements of the automotive and industrial markets. The HB2000 and HB2001 devices, as with most of NXP’s analog products, are included in NXP’s product longevity programme, which provides assurance of supply for a minimum of 10 or 15 years from the time of launch.