SEMA eNews Vol. 10, No. 27, July 5, 2007


Electronics and software represent more than 20% of the cost of today’s vehicles. Analysts project growth to 35% or even 40% by 2010. So according to WardsAuto, so-called embedded computing is growing as well.

Personal computers use a high-performance 64-bit microprocessor (MPU) as the central processing unit.  But embedded computing in vehicles consists of distributed elements for every system, and the computing power comes from microcontrollers (MCUs), digital signal processors (DSPs) and digital signal controllers (DSCs). Control systems such as powertrain, body electronics and safety typically have used 8-bit MCUs. However, some of today’s newer systems, such as hybrid-electric vehicle powertrains and advanced entertainment systems require the use of 32-bit MCUs.

In spite of the growing need for 32-bit MCUs, 8-bit units are the largest and still-growing portion of embedded automotive computers, according to the WardsAuto article. The more powerful 16-bit components are satisfying system requirements between the emerging low-cost 8-bit and high-performance 32-bit units. This is information that might prove useful for anyone manufacturing aftermarket components that require the use of microcomputers. 

DSCs, primarily used for motor controls, are yet another category of embedded computing. They are often used for electronic power steering, “where the brushless DC motor’s position is calculated based on feedback from steering-wheel position, torque and speed sensors.” Some of the latest embedded computers found in vehicles use 64-bit capability in order to address the stringent requirements of several new systems.

A new technology, field programmable gate arrays (FPGAs), allow system designers to configure programmable logic blocks. Some of these FPGAs have an embedded MCU core and/or DSP functionality.

The following table indicates the different types of computing units, their capabilities and their various applications. As vehicle systems become more and more complex, this type of information will be very useful.

Source:  Frank, Randy. (May 23, 2007). “Vehicle Electronics Growing by Bits and Bytes.” WardsAuto.  Retrieved June 25, 2007, from