GPTA - A Flexible New Timer Approach for Automotive Applications

Today's requirements for engine management controllers are increasing in various aspects. Stronger emission standards and diagnosis requirements demand more complex control algorithms, faster system response times, better usage of sensor information throughout the system and higher accuracy of actuator stimuli. Despite that, new solutions are needed to answer the requirement for higher cost effectiveness, flexibility and reusability. The trade-off between cost and functionality is constantly being reviewed when choosing the right microcontroller to operate with an ECU. Integration of more complex and flexible functionality into the microcontroller helps to reduce the need for custom ASICs and thus reduce the overall system cost. In order to reduce the demands on CPU throughput within the microcontroller, manufacturers have introduced smart peripherals that off-load some of the work of the CPU into the peripherals.

As many of these requirements are directly linked to the capabilities of embedded timer modules in a microcontroller, this paper shall discuss a novel building block timer approach with increased functionality, flexibility, accuracy, scalability and cost efficiency for automotive applications. The basics of the General Purpose Timer Array (GPTA) will be reviewed and its benefits compared to other timer modules that are currently offered. Typical automotive applications such as fuel injection, spark ignition and motor control will be used as examples for this comparison.