Thank you all for your responses on my heatsink question.

I didn't know how to read the databook w/ regards to heat.
Also, If I am using a 7805, and my source voltage is the car's battery,
at least is 13 volts when car is in operation, so 13v-5v=8Volt drop.
8*.75amp load = 6 Watts!!  6 watts * ~50 deg C per == 300 degree C.

Double that of a rated junction temperature of 150 Degrees C!!!

A switching power supply?  How about 2(or 3??) voltage regulators to step
down the voltage with less of a drop?  Are there any hang-ups with a
switching supply?  This is an automotive application, and noise can be
high.  I would like to keep parts count to a minumum.

Cya-

                         6500
                              7000
Dave Celsnak                    ___7500
                               / /     8000     (Shift!)
                             /-/
                           / /              RPM
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