Automotive clock generator facilitates high levels of safety

SiTime has introduced Chorus Automotive Clock Generators – the industry’s first fully integrated clock system-on-a-chip (ClkSoC) with built-in fault monitoring mechanisms for the complete clock generation signal path. The FailSafe technology in Chorus automotive provides a new approach to the industry, integrating a MEMS resonator, oscillator and advanced safety mechanisms into a single package. This integration simplifies system timing architecture and accelerates functional safety development time by up to six weeks. Hardware designers get the combined benefits of up to 10X higher performance in half the size compared to standalone oscillators and critical diagnostic coverage to attain functional safety metrics more easily.

Autonomous and semi-autonomous driving is becoming a reality, and the automotive industry is fast converging on the ultimate goal of SDVs. Whether implementing AD or ADAS, the technology fulfils the timing needs of safety-critical systems.

Timing Challenges Facing the Next-Generation of Automotive Design

Automotive engineers face unique challenges in implementing SDVs. Car buyers expect a user experience as seamless as smartphones but without compromising safety. As vehicles become more autonomous, hardware malfunctions are not merely annoying; they can also have serious consequences for life and property.

The ultimate SDV is a ruggedised datacentre-on-wheels. SDVs pipe in real-time information from sensors – cameras, Lidar, radar and more. The car is expected to process the data and make decisions instantaneously, prioritising safety for the people in the car and on the road. This HPC infrastructure supports 1000s of tera operations per second (TOPS). It needs a synchronous precision timing network with guaranteed reliable performance under shock, vibration, and extreme weather, with lifetimes spanning decades.

The company brings its pioneering leadership in ruggedised MEMS timing technology and synchronised high-precision timing networks for datacentres to the automotive space. Chorus automotive with an industry-first wide operating temperature range from -40C to 125C is uniquely positioned to remove any thermal bottlenecks in the design of safety critical modules.

Chorus automotive orchestrates complex timing for automotive compute and sensor systems by providing up to four configurable differential or up to eight single-ended low skew outputs. Its FailSafe technology enables ease of functional safety design by providing programmable end-to-end safety monitors. It is PCI Express (PCIe) Generations 1 - 6 compliant, with spread-spectrum options, on-chip regulators for extremely good power supply noise rejection, and phase-configurable and programmable skew outputs.

Chorus can alert an external safety manager MCU to any clock faults via configurable general-purpose I/O (GPIO) pins. The serial interface (I2C or SPI) can be used to read internal registers, including the status of the internal monitoring functions. These devices also facilitate high levels of flexibility using the in-system configuration (ISC) mode to modify the device configuration and each output behaviour via the serial interface.