Current Controller Having Programmable Current-Control Parameters And Hardware-Implemented Support Functions

摘要

A current-control profile suitable for the control of a solenoid actuator (for example figure 1) is built from a sequence of phases in which the current is controlled in a defined manner (figure 5). The electrical behaviour of these phases is configured within a list (figure 6), which contains one entry, or slot, for each phase and which are stored in a memory device. The order for stepping through the list is not hard-wired into the control circuit and is a part of the configuration for each entry itself. Each entry contains the information about the next phase, or the next possible phases depending upon the occurrence of any trigger events (figure 7). The linked list of entries is linked dynamically by pointers within the lookup table by the configuration allowing flexible generation of current profiles with different characteristics and different numbers of phases and sequences. The invention further comprises a current control signal employed in the enabling of the current source. The phase controller is hardwired to prevent execution of one or more loops (endless-loops) of phases in the list when the current control signal is de-asserted (disabled). Preferably when the control signal is de-asserted the controller will jump directly or indirectly towards the idle state, using only forward phase jumps. The current controller is primarily aimed at automotive fuel injectors, high pressure fuel pumps (HPFP) or direct inlet valves (DIV) all of which require a safety relevant specific sequence of controlled currents.