The basic mechanical design principles of the four-stroke internal combustion engine have remained essentially the same since patented in 1884. However, the electrical systems in automotive engines have changed dramatically over the years. Modern electronic control systems are designed to meet legislative mandated exhaust emission levels, provide competitive fuel economy, meet customer quality expectations and enhance the “fun to drive” factor.

The microcontroller, a powerful tool in these solutions, requires the support of devices that can interface with the harsh world of the engine, and its complement of electro-mechanical sensors, solenoids, relays, injectors, coils, motors, actuators and other power managing devices.

The following engine management block diagram illustrates, in a simplified way, the complexity of the engine control solution. The actual solutions represent multiple sensors, switches and “loads” to monitor and control, with complexity based on the engine size (i.e., number of cylinders).

Key Benefits

The new products illustrated in the gasoline and diesel engine management block diagram (above) possess capabilities that provide the flexibility that designers need to manage the functionality required for such complex controllers.