Multiplexing drive circuit for an ac ignition system with current mode control and fault tolerance detection

Abstract

A multiplexing drive circuit for an AC ignition system having a common leg that includes two switches coupled in series, and one or more dedicated legs, wherein each leg includes two switches coupled in series. The multiplexing drive circuit also includes a transformer for each of the one or more dedicated legs, each transformer having a primary winding coupled between one of the one or more dedicated legs and the common leg, and wherein each transformer has a secondary winding coupled in parallel to a spark plug, and a pulse-width modulated (PWM) switch controller configured to operate the common leg and dedicated leg switches to control characteristics of the spark discharge for the spark plug. Wherein the switch controller is capable of real time diagnostic checks by monitoring the time at which a spark discharge event takes place.

Dependencies are inferred from the claim text.