The new S32K39 series of automotive microcontrollers (MCUs) from NXP is optimised for electric vehicle (EV) control applications. With a combination of performance, integration, networking, security and functional safety, the new MCUs are focusing on traction inverter control – with performance headroom for further related tasks. The product family fits into zonal or domain E/E architectures that are central to the Software-Defined Car.
The S32K39 MCUs offers high- speed and high-resolution control for increased power efficiency to extend driving range and provide a smoother EV driving experience. Their architecture includes networking, security and functional safety capabilities beyond traditional automotive MCUs to address the needs of software-defined vehicles. The new MCUs enable NXP’s battery management system (BMS) and EV power inverters to provide end-to-end solutions for next-generation EVs.
The new MCU family is optimised for the intelligent and high-precision control of traction inverters that convert the EV battery’s DC power into alternating current to drive modern traction motors. The MCUs support traditional insulated-gate bipolar transistors (IGBT), as well as newer silicon carbide (SiC) and gallium nitride (GaN) technologies. With dual 200 kHz control loops to improve power efficiency, these can enable smaller, lighter, more efficient inverters, allowing motors to deliver a longer driving range. They can also control six-phase motors with increased power density and fault tolerance for improved long-term reliability. A safe ASIL D software resolver, along with integrated sine wave generation and sigma delta converters, eliminate external components for reduced overall system cost. The S32K39 also provides flexibility to control up to quad traction inverters when coupled with the NXP S32E real-time processor and can implement advanced traction capabilities for 4-wheel drive EVs in this configuration.
Because of its versatility, the S32K39 series is suited to address a wide range of EV applications beyond traction inverter control, including battery management (BMS), on-board charging (OBC) and DC/DC conversion, says Brian Carlson, responsible for NXPs global product and solutions marketing. With support for hardware isolation, time-sensitive networking and advanced cryptography, it is positioned to support software-defined vehicles and zonal architectures.
According to Carlson, the S32K39 is the highest performance member of the S32K family with four Arm Cortex-M7 cores at 320 MHz configured as a lockstep pair and two split-lock cores. Further details of the chip architecture include up to 6MB of flash memory and 800KB of SRAM. The integrated software resolver (safety level ASIL D) eliminates external components and reduces cost. Also integrated is a DSP for flexible digital filtering and machine learning (ML) algorithms.
For the communication with the outside world, the S32K39 is equipped with 6 CAN FD interfaces, TSN Ethernet and a decent number of programmable I/Os.
An integrated hardware security engine (HSE) ensures trusted boot, security services, secure over-the-air (OTA) updates using Public Key Infrastructure (PKI) and key management. For the sake of functional safety and cybersecurity, the product family is developed with certified ISO/SAE 21434 cybersecurity and ISO 26262 functional safety processes.
Also available is the S32K37 as a simpler version without the two motor control processors.