>This might seem like a stupid question, but I have a schematic that have
>some parts, including the PIC, grounded or whatever with a inverted
>triangle.  There is also a traditional ground symbol so my question is
>what is the inverted triagle?

The triangle symbol is a "circuit common" symbol. The ground symbol with
horizontal lines is an "earth ground". If both are used it usually means
they are not connected together but are common points for separate
circuits.

You usually see this where an optical isolator is used. The LED has one
grouns symbol and the phototransistor has the other indicating that the two
"grounds" may be hundreds of volts apart.

Eric Strauts - TEEM Electronics
E-mail:  102570.2265@compuserve.com