Long story short, I'm designing a little device to monitor a sensor or two in my car. I'm not an EE, but I'm a stickler for knowing things will work right and that I won't have wasted my time and money only to have my device fried by less-than-ideal power sources. :)
I've managed to cobble together a power supply circuit that incorporates both a surge stopper (LT4356) and a linear regulator (LT1963AEQ), with a nice TVS (SMAJ40A) sitting in front, to give me regulated +5V and hopefully withstand the mythical load dumps referred to in SAE articles and TVS datasheets all over the internet. :)
What I'm stuck on now is... how do I verify what I have is good? What could I do better?
I've had a few ideas on testing it: really mess with the circuit and attach high voltage DC supplies to the inputs... touch wires briefly and what not. I'd really like to know if this thing can survive an honest load dump, though.
As far as the design... is my TVS diode stout enough? Is there another approach I should take like shoving in a big cap or two to slow down the spikes and give the TVS less work to do? I've asked in IRC channels and perused the web... and I've seen everything from DC line filters to inductors to huge caps to diodes to tranzorbs and a million other things. I'm just slightly confused on what is considered a good baseline approach to protecting a circuit from the rigors of an automobile's DC power system.