| 摘要 |
An automotive ignition system includes a control circuit (52) operable to drive a coil current switching device (24) connected to an ignition coil (30) referenced at battery voltage. The control circuit (52) includes a drive circuit (20) and ring damping circuit (58) producing an inhibit signal (INH) to which the drive circuit (20) is responsive to control the state of the coil drive signal (GD). In a single pulse ignition system; i.e., an ignition system employing a single coil charging event per combustion cycle, the ring damping circuit (58) is responsive to a spark control signal (ESTBF) to control charging and discharging of a single capacitor (C1) to define the inhibit signal (INH). In a multiple pulse ignition system; i.e., an ignition system employing multiple coil recharging cycles following a standard initial charging dwell cycle, the ring damping circuit (58) is responsive to the spark control signal (ESTBF) and at least two mode signals (M1, M2) to control charging and discharging of the single capacitor (C1) throughout the initial and subsequent coil charging cycles to define the inhibit signal (INH). In either case, the drive circuit (20) is responsive to the inhibit signal (INH) to disable current flow through the primary ignition coil (30) when the inhibit signal (INH) is enabled, and to enable current flow through the primary ignition coil (30) when the inhibit signal (INH) is disabled.
|
