To improve efficiency of system
communication and to reduce cost, all
of today’s automotive designs employ
a variety of serial bus communication
protocols. The I
2C and SPI protocols
are most often used for chip-to-chip
communication within electronic
control units (ECUs).? For long-haul
serial communication between various
automotive subsystems such as
anti-lock brakes, airbag deployment,
engine control, and GPS navigation,
the CAN, LIN, MOST and FlexRay
protocols are the most popular serial
buses implemented in today’s vehicles,
as shown in Figure 1. Unfortunately,
long-haul communication is often
susceptible to signal integrity problems
caused by the naturally harsh
environment found in automobiles,
including signal interference from
ignition systems and random system
noise, which can sometimes create
errors during critical communication
cycles.
Introduction