Which one is the + and the - in an IC circuit (7812, 7912, 7805, 7905)?

Question

for electronics and power supply. which one is in the + and -? the one on the left or right?

Answer 1

http://www.sparkfun.com/commerce/tutoria...

In the above mentioned link you will find pictures of ICs, where input, output and groun pins are shown clearly. You can also search in net for more pictures.

Answer 2

These parts go in series with the supply. The 78 series are made to be + regulators, so they connect between the + unregulated supply and the + regulated output. They also have a ground pin.

The 79 series are for - supplies, and connect the same way. Between the - unregulated supply and the - regulated output. They also have a ground pin.

Download the data sheet, it shows you how to connect them in detail.

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