Patent ID: 6147849
Filing Date: 2000-11-14
Classification: F02B,F02P

Abstract:
A multichannel ignition circuit for controlling a supply of current to a plurality of ignition coils for use with an internal combustion engine, each of the ignition coils including a primary coil and a secondary coil, said multichannel ignition circuit comprising:a controller operable to generate a plurality of ignition timing pulses;a driver/switching circuit having a plurality of drivers, each of said drivers operable to be turned on upon receipt of one of said ignition timing pulses from said controller, each of the ignition coils operable to generate a firing voltage upon one of said drivers being turned on;a current limiting circuit operable to regulate an amount of current through each of the ignition coils when the internal combustion engine is operating below a threshold, said current limiting circuit includes an operational amplifier having a feedback loop that includes a capacitor C; anda peak voltage reduction circuit forming a part of said current limiting circuit, said peak voltage reduction circuit operable to reduce voltage peaks in each of the ignition coils when said current limiting circuit is regulating the amount of current through each of the ignition coils and one of said ignition timing pulses is on, said peak voltage reduction circuit includes a voltage divider formed by a first resistor and a second resistor and a diode in said feedback loop of said operational amplifier, wherein said peak voltage reduction circuit reduces the charge on said capacitor C.