Ignition system control circuit

Abstract

The invention discloses an ignition system control circuit which may be mounted within a distributor housing such as is used with internal combustion engines. The ignition system control circuit is coupled to a direct current source and appropriately connected to the primary winding of the high voltage generating coil of the ignition system. Current through the primary of the high voltage generating coil is controlled by a Darlington power amplifier, the conduction and non-conduction of which is appropriately synchronized to the engine. The control circuit includes a constant current source connected to a biasing resistor network of the Darlington power amplifier, and the constant current source supplies the Darlington power amplifier with a value of current to assure saturation of the Darlington power amplifier to allow maximum current to flow through the primary winding of the ignition coil notwithstanding substantial variations in voltage of the direct current source. The ignition system control circuit further includes a feedback loop to provide increased gain during switching.