Enhancing Automobile Audio Networks via Ethernet-AVB

Automotive Ethernet has the capacity needed to support data transfer rates that are orders of magnitude higher than legacy CAN/LIN-based in-vehicle networking protocols. This will be highly advantageous, as new functionality starts to be designed into automobiles and new zonal and central architectures. Numerous sensors and cameras, including sophisticated LiDAR imaging systems, need to be integrated into the new car networking architectures along with audio for the infotainment and communication system. Adoption of Ethernet technology for in-vehicle networking will make it possible for separate cabling for multimedia functions to be dispensed with - leading to space and cost savings. The Ethernet audio video bridging (AVB) extension has been implemented for precisely this reason. This complements the other time sensitive networking (TSN) protocols that are being incorporated to address safety functions.

Thanks to the extensions by AVB/TSN, Ethernet is now able to ensure that deterministic operation is adhered to throughout the vehicle’s multimedia systems. The speakers serving each individual sound zone inside the vehicle cabin (for example) will operate in unison and unwanted sound artefacts will not occur.  

To simplify the implementation of AVB audio applications, it helps to have a single small silicon interface chip solution that is capable of meeting the needs of all the connected nodes on the network. Through the introduction of its TC9562 interface ICs, Toshiba is helping to facilitate easy and straight forward AVB audio architecture implementation within vehicles, so car manufacturers can gain traction from such functionality. Each of these AEC-Q100 compliant devices fully supports the IEEE’s 802.1AS precision timing and 802.1Qav data stream queuing protocols - both of which are pivotal to AVB operation and even TSN. They feature a small Arm® Cortex®-M3 processor core and implemented audio hardware for transfers between TDM and Ethernet audio protocols, including an integrated audio-PLL with Media-Clock recovery system. The TC9562 can work as a small standalone interface chip at SoCs and in remote audio units and allows the multimedia nodes in the car’s network to work together for even complex Ethernet-based car-audio systems. If you would like to learn more about AVB audio in an automotive context, why not read Toshiba’s highly informative whitepaper on the subject. It can be downloaded below: