telematics control unit (automotive) (TCU)

A Telematics Control Unit (TCU) is a control device in motor vehicles. A TCU unit establishes the connection between vehicle electronics and the Internet. It has its own memory, its own bus systems, controllers for fieldbuses and wireless networks, PC-compatibleinterfaces such as the USB interface or 1394, with A/D converters, I/O interfaces and much more.

TCU units are central components in vehicle wiring systems. They process the data they receive via the connected fieldbuses, such as the CAN bus or the MOST bus, control the actuators and transmit the data to the driver assistance system, where it is shown on the displays. Several CAN buses with different transmission rates for different applications can be connected to the TCU unit. For example, a slow CAN bus to which the sensors and actuators are connected via a LIN bus, or a fast CAN bus for the powertrain with the ignition, engine and transmission control. In addition, the media network, which supports infotainment via the MOST bus, is connected.

For the display instruments and the dashboard, further bus systems are available in the form of the LIN bus, I2Cbus, SPI bus (Serial Peripheral Interface) or Microwire, which are controlled by the TCU units. In addition to the wired networks, components can also be connected wirelessly to the fieldbuses via ZigBee or Bluetooth. For example, the tire pressure sensors to the slower CAN bus for the sensors and actuator controls. The TCU units form the gateway between the fieldbuses and support the various protocols of these fieldbuses.