In a recent project where I have a 10F200 driving a FET driving a 12VDC
motor, I looked at various ways to get the 5V for the 10F200. Dealing with
automotive rated regulators turned out complex and expensive (big
capacitors required). The only load here is the 10F200 and the gate drive
to the FET (10F200 through a resistor), so I just did a zener regulator
(two series resistors, zener to ground, 1uF ceramic across the zener). I
think this should do fine in an automotive environment. The zener provides
reverse battery protection, the RC provides spike protection in case the
zener is not fast enough.

We'll see how it works!

Harold


-- 
FCC Rules Updated Daily at http://www.hallikainen.com - Advertising
opportunities available!
-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist