1. Field of the Invention
The present invention relates generally to the art of spark ignitions. In particular, the present invention relates to a circuit for generating and monitoring an energy signal proportional to the amount of energy delivered to the at least one spark plug. The present invention further generates and monitors a breakdown voltage signal of at least one spark plug.
2. Description of the Related Art
Two major challenges facing automobile manufactures today are fuel economy improvement and reduced emissions. One engine subsystem that could be refined to aid in meeting both of these challenges is the ignition system. Under current engine design techniques, electronic ignition systems are controlled by a microprocessor based controller or Electronic Control Unit (ECU). The controller reads a plurality of sensor inputs such as the crankshaft sensor, camshaft sensor, manifold absolute pressure sensor, throttle position sensor, coolant sensor, etc. and can thereby calculate the appropriate time to fire a spark in each cylinder.
The design of future ignition systems requires the implementation of an optimized solution for ignition requirements versus componentry size, weight, and costs. To accomplish such a task requires a better understanding of the ignition phenomenon and the associated critical parameters. Two of the most critical ignition parameters are the breakdown voltage and the energy levels required for combustion under various engine conditions. Previously, in the art of ignition systems, an ignition circuit has not existed whereby a spark plug energy signal is generated that is scaled in proportion to spark plug energy. In addition a circuit is also needed for capturing the spark plug breakdown voltage while being able to reset the circuit given a separate ignition event. Moreover, it is also highly desirable to have a circuit that monitors the spark plug energy and adaptively changes the amount of spark plug energy.