FlexRay, which started out as a time-triggered network protocol for automotive drive-by-wire applications, has graduated into much more. Despite the slow acceptance of drive-by-wire technology, automotive engineers are designing FlexRay hardware into a wide variety of automotive projects. BMW recently incorporated it into its X5 Sports Activity Vehicle, and other automakers are said to be employing it for such applications as chassis management, steering, engine management, braking, air bag management and adaptive cruise control.
The primary reason for FlexRay's growing customer base is its deterministic, fault-tolerant nature and its 10-Mbit/sec data rates. Because it offers increased network throughput, it reportedly can help cut costs and reduce the number of parallel CAN networks now being used to solve bandwidth bottlenecks.
“The X5 is now on the road, but that's just the tip of the iceberg,” says Toni Versluijs, NXP Semiconductors' business development manager for in-vehicle network controllers and FlexRay. “Several more carmakers are working behind the scenes and have FlexRay on the drawing board.”
Here are three recent FlexRay controllers and transceivers from NXP Semiconductors, Texas Instruments and Freescale Semiconductor.
Freescale's 16-bit FlexRay Microcontroller
Freescale's MC9S12XF family, also debuting on BMW's X5, provides a distributed control solution for embedded nodes on FlexRay networks used in body, chassis and safety applications. The family features four MCUs offering a variety of memory configurations and Freescale's XGATE co-processor. Package options range from the 112-pin low-profile quad flat-pack (LQFP) device to the 10 × 10 mm to the 64-pin LQFP.
NXP's 'World's First' FlexRay Transceiver
Employed on BMW's X5 vehicle, NXP's new TJA1080 is said to be the world's first FlexRay transceiver. Primarily intended for communication systems from 1 to 10 Mbit/sec, the TJA1080 provides an advanced interface between the protocol controller and the physical bus in the FlexRay network. It can be configured as a node transceiver or as an active star transceiver with only one device.
TI's Dual-Core FlexRay Chip
Texas Instruments' dual-core TMS570 MCU platform uses two identical ARM Limited Cortex R4 cores combined with an initial 2 Mbytes of on-chip Flash memory. Co-developed with Robert Bosch GmbH, its targeted applications include chassis control, braking, electronic vehicle stability control and steering. The dual cores are tightly coupled by a patent pending architecture. The FlexRay networking protocol is implemented directly on the device.