One particular automotive voltage requirement seems to have taken

care of itself. The auto power amplifier was suppose to be able to

withstand a -6 volts applied across its supply leads. This test was

to allow someone to accidentally connect a car battery up backwards

without doing any serious damage. A person making such a mistake

would know it immediately in that the alternators diodes would become

forward biased and would attempt to short out the battery. The

6volt number represents how well the diodes could shorted out a

car battery. I have seen a physic instructor vaporize a nail with a

car battery.



While the -6 volt supply spec caused little trouble for

the LM383, it meant that all the other electronics in a car needed

to voltage regulator that could provide protection. Some one made

the joke that the lateral PNP's were so bad that even delco would

not be able to destroy them. A skunk works layout of a lateral

PNP regulator ultimately made its way to delco. And sure enough,

they could not destroy it. They loved it. And National Semiconductor

got into the business of making PNP output regulators.

