How can I simulate and handle an automotive load dump?
The "correct" way to test your circuit is with a "load-dump generator" - for example, the LD200N load dump generator.

Load-dumps are actually pretty rare though - you need to worry much more about the other ISO pulses (eg the +-200V fast spikes which the TVS won't have chance to clip much) - don't know how fast the LT4356 will switch.

Those fast pulses tend to happen on many journeys as they can be caused by things like switching the wipers on and off, or the aircon compressor switching for example.

EDIT: I've looked at the TVS datasheet:

Your TVS claims a "response time" of 1ps.  I find that very hard to believe given that the package is 13ps long at the speed of light! I'd be interested to know how they measure it.

Anyway, the amount of series inductance there will be in circuit with it just from wiring and strays will slow that significantly.

Also, check out figure 1 - a load dump pulse can last a few hundred ms, two orders of magnitude to the right of that graph, which looks to halve the power for each 100x on the x-axis, so is more like a 200W device.  It may well be a good device for the fast pulses though!

(This is the sort of monster fitted to some automotive ECUs: )

Vishay have what looks like a reasonable read on the subject of automotive transients



As a teenager I built a bargraph revcounter and that survived fine for many years without load-dump, or indeed much else, protection.  Now I'm a proper engineer designing automotive products, I shudder when I think about it :)