The Integrated Circuit Division of Siemens Components Inc reckons the market for 16-bit microcontrollers will outstrip that for 8-bit ones within the next few years and it is preparing itself to take a major share. It has added two 16-bit microcontrollers, each with 4Kb of on-board RAM, double the amount of memory in their predecessor, to its C167 family, one of which is specifically aimed at providing high-level control for cars. The SABC167CR has an on-chip interface to the control area network protocol, which is steadily becoming the worldwide networking protocol for cars. It has a separate module controller that contains 15 message objects that perform error checking and send-receive messages, relieving the microcontroller from these tasks and further increasing processing speed and efficiency. The protocol’s popularity stems from its multiplexing capabilities, which ensure that several controllers can all use the same bus. This means the amount of wiring between microcontrollers can be reduced, and cabling is also reduced, which keeps costs down and reduces the weight of the finished vehicle. It also has high noise rejection capabilities, also attractive to car makers, as the environment in which they are used is packed with multiple signals. The microcontroller is also finding favour in industrial control systems and applications where there is a need for microcontrollers to communicate. Siemens said that within a car the CR microcontroller could be used to control other lower level processors as it is likely to be the highest performance controller in any system, or individually to control things like anti-lock brakes, transmission, active suspension and dashboard instrumentation. The other microcontroller launched is the SABC167SR, which has the same functions but does not have the network protocol interface. It’s being targeted at single microcontroller-based applications such as printers, telecommunications and medical usages. Other features the two products share are self-calibrating, 10-bit analogue-to-digital converters, each equipped with 16 analogue input channels. The self calibration eliminates offset error and linearity errors, enabling for greater accuracy over a wide temperature range. They also have a phase locked loop oscillator with an internal multiplier, which enables 20MHz clock operation but with only a 5MHz external clock crystal which makes its implementation easier and cheaper. Other features in the controllers include 111 input-output lines; an address range of up to 16Mb; four independent channels of 78KHz pulse width modulation at 8-bit resolution; 32 independent channels of capture-compare; an extended interrupt system with 55 interrupt sources with 36 external interrupts, of which eight interrupts have a very fast 50ns sample time. Although the company reckons the 16-bit market will be strong for a time to come, it is already working on 32-bit controllers. It said the market is still too cost- and space-sensitive to be much interested in the more powerful version, but it reckons that it will be in a couple of years. The SABC167CR is available in 1,000-piece quantities for $35 and 1,000-piece quantities for $31.
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