"CAN Partial Networking is an area where we see great potential for energy savings,” says Ricky Hudi, managing E/E director at carmaker Audi, at the June announcement. “In addition, intelligent wake-up concepts improve the lifetime of ECUs and increase the operating reach of electrical vehicles. Audi and Volkswagen corporations have therefore started to introduce Partial Networking into the next generation of car models. Audi estimates a mid-term reduction potential on CO 2 emissions of about 2.6 g/km and fuel savings of 0.11 litres/100km, when using CAN Partial Networking."
Fig. 1: Many CAN nodes are good candidates for non-continuous operation.
Partial CAN networking enables car designers to put CAN nodes into a sleep mode. In this mode they consume far less power than in active mode. Examples are door modules, sun roof controllers or trailer coupling controllers. In standard CAN configurations these controllers are constantly active - in the case of the trailer coupling even when no trailer is used. Under partial networking these controllers can be put to sleep mode, but if required they can be reactivated within few milliseconds - fast enough that no driver would notice the difference, explained Kurt Sievers, Senior Vice President and General Manager of NXP Semiconductors' automotive business unit.
NXP now has introduced two CAN chips supporting partial networking mode. The stand-alone TJA1145 CAN transceiver and system basis chip UJA1168 are the first highly integrated solution to support CAN Partial Networking, claims NXP. According to the vendor, theygive design engineers precision control over a vehicle's bus communication network. By intelligently de-activating those Electronic Control Units (ECUs) that are currently not needed, engineers are able to significantly reduce vehicle fuel consumption and CO2 emissions without sacrificing performance or consumer experience.
Kurt Sievers, senior vice president and general manager Automotive, NXP Semiconductors, comments: “CAN Partial Networking is a real game-changing innovation in in-vehicle electronics, enabling a level of intelligent control over ECUs not previously possible.