| 摘要 |
The aim of the invention is to provide an especially cost-effective and yet reliable device for controlling at least one piezoactuator (P) for an injection valve of an internal combustion engine. For this purpose, a microcontroller (M) controls a final stage (E) which generates the load current (Ip) for charging and discharging the piezoactuator (P). The microcontroller (M) controls the final stage (E) not directly but via an integrated circuit (A) which is especially provided for this purpose. A discharge circuit (D) is configured in a particular manner and interacts with the integrated circuit (A) in a particular manner, and reliably discharges the piezoactuator (P) in case of a failure of the final stage (E) and/or of the microcontroller (M) ("safety path"). The load current (IP) flowing during this discharge is defined by a control circuit, the controller (R) of which is contained in the integrated circuit (A). The discharge circuit (D) comprises emergency discharge elements (T3, T4, R7, R8, D2, I1, I2, M') that are activated in case of a failure of the controller (R) or of the integrated circuit (A). |
