GND & VCC pin on IC

Question

This is for most of you probably the most obvious thing in designing.............. but I as a newbee have this question :

I take a LM 1458 from the library onto the schematic, I select both opamps, and start connecting........ but there is no VCC or GND, (although they are drawn in the library drawing) I have named the plus and minus leads of the circuit VCC and GND nothing , also in info on the 1458 is no mention of vcc or gnd, even in the help I could not find a hint

then in the board is also no airwire to one of both pins?????

What is the "golden grip" that I have missed?

Jack

autodeskguest · Accepted Answer

On 16/12/13 21:16, jack asnack wrote:

This is for most of you probably the most obvious thing in
designing.............. but I as a newbee have this question :

It is a very common newbie question.

I take a LM 1458 from the library onto the schematic, I select both
opamps, and start connecting........ but there is no VCC or GND,
(although they are drawn in the library drawing)

No, they're not. The pins you see on the control panel are called 'V+'

and 'V-'

I have named the plus
and minus leads of the circuit VCC and GND nothing , also in info on the
1458 is no mention of vcc or gnd, even in the help I could not find a
hint

No, as I said, they're not called that.

then in the board is also no airwire to one of both pins?????

What is the "golden grip" that I have missed?

Two things.

The pins are named V+ and V-, so to get Eagle's automatic power supply

connection (which some people really dislike) you need to place supply

symbols V+ and V- on your schematic.

If you want to have the pins shown on the op-amp, as they appear in the

library diagram, you need to use "invoke". Check the help for how to do

that.