> On Tue, 9 Sep 2003 05:05:05 -0400, Richard Graziano wrote:

>> The double d is for drain.  The double s is for source.  In field effect
>> devices the terminals are gate g, drain d, and source s.

> And what's a good way to remember which is which?  To my mind, "drain" should be at the
> bottom, but I think this is wrong.  Anyone have a good mnemonic?  I do wish they'd call it
> V+ and V0 - I'm really not intested in the technology behind the pin when I'm working out
> where to put the power & earth (especially when getting it backwards is a Bad Thing)!

Transistors in general have an electrode which produces charge carriers, one which
modulates the flow, and one which receives the carriers at the other end. The names
given to the electrodes reflect (more or less) their function.

In a bipolar transistor, carriers are released from the EMITTER, modulated by the BASE
(the one exception in which name does not follow function), and received at the
COLLECTOR.

In a FET, charge is released from the SOURCE, modulated by the GATE (relevance finally),
and received at the DRAIN.

There is even a high frequency device with an INJECTOR. Guess which electrode it
corresponds to.

John Power

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