I am trying to design an input power supply filter circuit inorder to protect from ISO 7637 pulses.
I am referring this Little fuse app note
There seem to be different pulses. Pulse 1, 2a, 2b and so on.
In page two of the app note, they have given the description of the pulses.
Why are some pulses negative and some pulses positive? I just want to understand how some pulses can be positive and can be negative
Can someone explain in simple terms regarding the pulse 1 and pulse 2 description in page 2? Like please explain "disconnection of the power supply from an inductive load " and "Interruption of series inductive load"? Any block diagram or explanation with the concept and direction of current and voltage would be very helpful to me.
Quotes phrases are verbatim.
(P.S. I understand when an Inductive load is disconnected, we need to protect DUT with the help of a flyback diode to prevent from heavy voltage build-up. Is this the reason why some voltage pulses are positive and some are negative.)