Other Parts Discussed in Thread: DRV110
I have a requirement for a specific injector that wants the peak current drive to be held at 3A for 2 mS followed by the drop to the hold current level of 0.75A.
From what I can tell from reading the datasheet, the LM1949 drives Q1 hard on until it sees 385 mV across the sense terminals and then goes down to the 1/4 holding current; is this right?
Is there some way to extend the length of the peak pulse perhaps by delaying the voltage over Rs getting to the sense terminals using an RC time delay? When I thought about this it concerned me that the current being drawn by the injector would be uncontrolled for 2 mS and could over-drive the injector. It would also mean a delay in the regulation down to the holding current but that would be a lesser concern.
Any help and suggestions would be appreciated.
Ted
