On Sat, 21 Jan 2012 21:23:33 +0800, the renowned Rheilly Phoull
wrote:



I don't understand the problem. I have been using the 7809 etc. for
years in the automotive situation without a single failure.
It's not exactly rocket science

Rheilly P

It's not rocket science, but there are some subtleties:-

http://www.vishay.com/docs/88490/tvs.pdf

A few parts (series 1N400x, series power resistor, parallel TVS) will
protect the regulator against +/-100V transients and reverse wiring.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
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