Capacitor discharge ignition circuit

Abstract

An emission control circuit for an internal combustion engine having a voltage generating circuit connected to a source of direct current energy at a first potential for generating an output voltage of a substantially higher potential, the voltage generating circuit including energy storage means coupled to the output of the voltage generating means for storing an electrical charge. A triggerable switching means is provided for coupling the energy storage means in series with the primary winding of an induction coil, and triggering means responsive to the opening and closing of ignition breaker points is provided for applying triggering signals to the triggerable switching means. The triggering signals accommodate discharging of the energy storage means through the primary winding for a certain predetermined time period. A comparator circuit is provided which includes two semiconductor amplifier circuits, each having a pair of output electrodes and a control electrode. The comparator circuit is operable for inhibiting the triggering signals upon opening of the key switch, thus preventing triggering of the triggerable switching means when the key switch is opened.