Use Grows as Size Shrinks

Automotive engineers continue to use electronics to add features and functions, driving growth for processor suppliers. While much focus is on high-end devices, 8-bit chips continue to see solid acceptance.

The automotive market is by far the largest user of 4- and 8-bit processors, which will continue to outship their high-end brethren, according to Dataquest Gartner (http://rbi.ims.ca/3851-517). In 2006, 8-bit shipments (with a fraction of 4-bit devices) will hit $3.9 billion, compared to $3.5 and $1.9 billion for 16- and 32-bit microcontrollers, respectively.

Even in demanding applications such as airbags, where processing must happen in milliseconds, their low cost and high power continues to earn them design spots. "We're using 8-bit microcontrollers in a variety of restraint products including airbag systems," said Thomas Stierle of Siemens VDO Automotive's Restraint Systems group in Auburn Hills, MI (http://rbi.ims.ca/3851-518).

The growing number of airbags is among many applications that are keeping 8-bit volumes high.

"Approximately 50 percent of the processors in vehicles are 8-bit chips, it's still a growing area," says Willie Fitzgerald, automotive products marketing director at Chandler, AZ-based Microchip Technology (http://rbi.ims.ca/3851-519).

Market watchers say there's still plenty of potential for small 8-bit microcontrollers to convert mechanical control functions by using electronic features. "There's always a place for mechatronics, adding a processor to sensors or actuators. As price comes down, that certainly becomes more attractive," says Paul Hansen of the Hansen Report on Automotive Electronics (http://rbi.ims.ca/3851-520).

Microchip recently shrank an 8-bit processor down to a 6-pin SOT-23 package that it says is the smallest packaged CPU (see DN 06.07.04; http://rbi.ims.ca/3851-521). Aimed at tier 1 automotive suppliers such as Bosch, Siemens VDO, and Delphi, the PIC10F holds 512 words in flash and 24 bytes of SRAM.

"The primary role is inside the car, either as an instrument or to create an atmosphere," says Fanie Duvenhage, product marketing manager for Microchip's Security, Microcontroller and Technology Development Division. The microprocessor creates various frequencies for chimes and other alerts, while lighting controls handle slow ramping and dimming, providing more capability than electromechanical controls, he adds.

Another potential application is to replace a watchdog timer, giving designers more flexibility and capability, Microchip's Fitzgerald says. The chip has a built-in timer, so programmability for extra functions can be added without increasing size. In these and other applications, the chip can replace a number of discrete components.

With the chip's price as low as $0.49 in quantity, "The cost is often comparable to a few logic gates and transistors," says Duvenhage.

In addition to its small size and price, marketers tout the simplicity of using a processor instead of components. "Engineers can design this in faster than they can find the perfect combination of discrete parts," Duvenhage says.

Still Growing: Eight-bit controller use continues solid growth in automotive applications, spearheaded by burgeoning airbag systems.